Labour and Delivery Flashcards
How do you describe gravidy and parity?
What is a wood uterus which is painful on palpation indicative of?
Placental abruption
What is chorioamnionitis
Infection of the membranes in the uterus
Typical signs: maternal and feotal tachycardia, Pyrexia and uterine tenderness
Typical symptoms: fever abdominal pain offensive Vaginal discharge
Indications for admission and delivery
When should delivery be aimed for in Obstetric choleostasis?
37-38 weeks
Classic triad of amniotic fluid embolism
Coagulopathy, hypoxia and hypotension
What is the most popular analgesia for mild labour pain and what advantages does it have?
Entonox (1:1 inhaled NO and O2)
Does not interfere with endogenous oxytocin nor labour progression.
Does not cross placenta readily therefore does not affect foetal HR nor newborn respiratory rate
What might be required if pre eclampsia complications occur of maternal BP cannot be controlled?
Planned early birth may be necessary if the blood pressure cannot be controlled or complications occur.
What should be given to women having a premature birth to help mature fetal lungs?
Corticosteroids
At what point following delivery will blood pressure return to normal in a woman with pre eclampsia?
Blood pressure is monitored closely after delivery. Blood pressure will return to normal over time once the placenta is removed.
Pre eclampsia management following delivery?
For medical treatment, NICE recommend after delivery switching to one or a combination of:
Enalapril (first-line)
Nifedipine or amlodipine (first-line in black African or Caribbean patients)
Labetolol or atenolol (third-line)
Braxton-Hicks contractions
Braxton-Hicks contractions are occasional irregular contractions of the uterus. They are usually felt during the second and third trimester. Women can experience temporary and irregular tightening or mild cramping in the abdomen. These are not true contractions, and they do not indicate the onset of labour. They do not progress or become regular. Staying hydrated and relaxing can help reduce Braxton-Hicks contractions.
What is ‘the show’?
The “show” refers to the mucus plug in the cervix, that prevents bacteria from entering the uterus during pregnancy, falling out and creating space for the baby to pass through.
What is meant by presentation?
Presentation: the part of the fetus closest to the cervix
Types of presentation?
Cephalic presentation – the head is first.
Shoulder presentation – the shoulder is first.
Breech presentation – the legs are first. This can be:
Complete breech – with hips and knees flexed (like doing a cannonball jump into a pool)
Frank breech – with hips flexed and knees extended, bottom first
Footling breech – with a foot hanging through the cervix
Types of lie?
Longitudinal lie – the fetus is straight up and down.
Transverse lie – the fetus is straight side to side.
Oblique lie – the fetus is at an angle.
What is meant by lie?
The position of the fetus in relation to the mother’s body
What is meant by attitude of the fetous?
the posture of the fetus. For example, how the back is rounded and how the head and limbs are flexed.
What are the seven cardinal movements of labour?
Engagement
Descent
Flexion
Internal Rotation
Extension
Restitution and external rotation
Expulsion
dWhat is descent and how is it measured?
Obstetricians describe the position of the baby’s head in relation to the mother’s ischial spines during the descent phase. Descent is measured in centimetres, from:
-5: when the baby is high up at around the pelvic inlet
0: when the head is at the ischial spines (this is when the head is “engaged”)
+5: when the fetal head has descended further out
Signs of labour?
Show (mucus plug from the cervix)
Rupture of membranes
Regular, painful contractions
Dilating cervix on examination
Latent first stage of labour
Painful contractions
Changes to the cervix, with effacement and dilation up to 4cm
Established first stage of labour
Regular, painful contractions
Dilatation of the cervix from 4cm onwards
Established vs latent first stage of labour
Established: contractions are REGULAR, cervix dilated from 4cm onwards
From which point until when is the first stage of labour
The first stage of labour is from the onset of labour (true contractions) until the cervix is fully dilated to 10cm.
What is considered the latent phase of first stage of labour, and how quickly does it progress?
from 0 to 3cm dilation of the cervix. This progresses at around 0.5cm per hour. There are irregular contractions.
What is considered the active phase of first stage of labour and how quickly does it progress?
from 3cm to 7cm dilation of the cervix. This progresses at around 1cm per hour, and there are regular contractions.
What is considered the transition phase of the first stage of labour and how quickly does it progress?
from 7cm to 10cm dilation of the cervix. This progresses at around 1cm per hour, and there are strong and regular contractions
Cervical changes in first stage of labour?
It involves cervical dilation (opening up) and effacement (getting thinner).
Labour and delivery normally occur between how many weeks gestation?
37 and 42 weeks gestation.
Role of oxytocin during labour?
Oxytocin stimulates the ripening of the cervix and contractions of the uterus during labour and delivery.
When might an oxytocin infusion be used?
Induce labour
Progress labour
Improve the frequency and strength of uterine contractions
Prevent or treat postpartum haemorrhage
What is Syntocinon?
Brand name of oxytocin
What is Atosiban and when might it be used?
Atosiban is an oxytocin receptor antagonist that can be used as an alternative to nifedipine for tocolysis in premature labour (when nifedipine is contraindicated).
What is Ergometrine and when is it used?
Ergometrine is derived from ergot plants. It stimulates smooth muscle contraction, both in the uterus and blood vessels.
This makes it useful for delivery of the placenta and to reduce postpartum bleeding. It may be used during the third stage of labour (delivery of the placenta) and postpartum to prevent and treat postpartum haemorrhage.
It is only used after delivery of the baby, not in the first or second stage.
Ergometrine Side Effects
Due to the action on the smooth muscle in blood vessels and gastrointestinal tract, it can cause several side effects, including hypertension, diarrhoea, vomiting and angina
In what conditions can ergometrine not be used/be used with significant caution?
It needs to be avoided in eclampsia, and used only with significant caution in patients with hypertension.
What is Syntometrine and what can it be used to treat?
Syntometrine is a combination drug containing oxytocin (Syntocinon) and ergometrine. It can be used for prevention or treatment of postpartum haemorrhage.
Dinoprostone, which is prostaglandin E2, can come in which three forms?
Vaginal pessaries (Propess)
Vaginal tablets (Prostin tablets)
Vaginal gel (Prostin gel)
What is misoprostol and when is it used?
Misoprostol is a prostaglandin analogue, meaning it binds to prostaglandin receptors and activates them. It is used as medical management in miscarriage, to help complete the miscarriage. Misoprostol is used alongside mifepristone for abortions, and induction of labour after intrauterine fetal death.
What is Mifepristone and when is it used?
Mifepristone is an anti-progestogen medication that blocks the action of progesterone, halting the pregnancy and ripening the cervix. It enhances the effects of prostaglandins to stimulate contraction of the uterus. Mifepristone is used alongside misoprostol for abortions, and induction of labour after intrauterine fetal death. It is not used during pregnancy with a healthy living fetus.
What is Nifedipine and when is it used in pregnancy?
Nifedipine is a calcium channel blocker that acts to reduce smooth muscle contraction in blood vessels and the uterus. It has two main uses in pregnancy:
Reduce blood pressure in hypertension and pre-eclampsia
Tocolysis in premature labour, where it suppresses uterine activity and delays the onset of labour
What are tocolytics?
Tocolytics are medications used to suppress premature labor.
What is Terbutaline and when is it used?
Terbutaline is a beta-2 agonist, similar to salbutamol. It stimulates beta-2 adrenergic receptors. It acts on the smooth muscle of the uterus to suppress uterine contractions. It is used for tocolysis in uterine hyperstimulation, notably when the uterine contractions become excessive during induction of labour.
What is carboprost and when is it used?
Carboprost is a synthetic prostaglandin analogue, meaning it binds to prostaglandin receptors.
It stimulates uterine contraction. It is given as a deep intramuscular injection in postpartum haemorrhage, where ergometrine and oxytocin have been inadequate.
In which patients should carboprost be avoided/used with particular caution?
Notably, it needs to be avoided or used with particular caution in patients with asthma, as it can cause a potentially life-threatening exacerbation of the asthma.
In which patients should carboprost be avoided/used with particular caution?
Notably, it needs to be avoided or used with particular caution in patients with asthma, as it can cause a potentially life-threatening exacerbation of the asthma.
What is tranexamic acid and when might it be used in delivery?
Tranexamic acid is an antifibrinolytic medication that reduces bleeding. It binds to plasminogen and prevents it from converting to plasmin. Plasmin is an enzyme that works to dissolve the fibrin within blood clots. Fibrin is a protein that helps hold blood clots together. Therefore, by decreasing the activity of the enzyme plasmin, tranexamic acid helps prevent the breakdown of blood clots.
Tranexamic acid is used in the prevention and treatment of postpartum haemorrhage.
What can improve pain symptoms in labour without the used of medications?
Understanding what to expect
Having good support
Being in a relaxed environment
Changing position to stay comfortable
Controlled breathing
Water births may help some women
TENS machines may be useful in the early stages of labour
Hyponobirthing
Music therapy
Simple analgesia in early labour?
Paracetamol is frequently used in early labour. Codeine may be added for additional effect. NSAIDs are avoided.
What is Gas and air (Entonox) and how is it used?
Gas and air contains a mixture of 50% nitrous oxide and 50% oxygen.
This is used during contractions for short term pain relief.
The woman takes deep breaths using a mouthpiece at the start of a contraction, then stops using it as the contraction eases.
Entonox side effects?
It can cause lightheadedness, nausea or sleepiness.
What opioid medications can be used in labour which may also help with anxiety and distress?
Pethidine and diamorphine, usually given by intramuscular injection.
Considerations when using PCA for patients in labour?
Patient-controlled analgesia requires careful monitoring. There needs to be input from an anaesthetist, and facilities in place if adverse events occur. This includes access to naloxone for respiratory depression, and atropine for bradycardia.
What might be given as PCA for a woman in labour?
Patients may be offered the option of patient-controlled intravenous remifentanil. This involves the patient pressing a button at the start of a contraction to administer a bolus of this short-acting opiate medication.
What is an epidural, and where is it placed?
An epidural involves inserting a small tube (catheter) into the epidural space in the lower back. This is outside the dura mater, separate from the spinal cord and CSF.
Local anaesthetic medications are infused through the catheter into the epidural space, where they diffuse to the surrounding tissues and through to the spinal cord, where they have an analgesic effect. This offers good pain relief during labour.
What are the anesthetic options for use in an epidural?
Levobupivacaine or bupivacaine, usually mixed with fentanyl.
What are the potential adverse affects of an epidural?
Headache after insertion
Hypotension
Motor weakness in the legs
Nerve damage
Prolonged second stage
Increased probability of instrumental delivery
Why do women with an epidural need urgent anaesthetic review if they develop significant motor weakness (unable to straight leg raise)?
Headache after insertion
Hypotension
Motor weakness in the legs
Nerve damage
Prolonged second stage
Increased probability of instrumental delivery
The third stage of labour is from the completed birth of the baby to the delivery of the placenta. What are the two options for the third stage?
PHYSIOLOGICAL MANAGEMENT - placenta is delivered by maternal effort without medications or cord traction
ACTIVE MANAGEMENT - midwife or doctor assist in delivering of the placenta.
Active management of third stage of labour?
Patient given a dose of intramuscular oxytocin to help the uterus contract, and careful traction to the umbilical cord to guide the placenta out of the uterus and vagina.
Intramuscular dose of oxytocin (10 IU) after delivery of the baby.
The cord is clamped and cut within 5 minutes of birth. There should be a delay of 1 – 3 minutes between delivery of the baby and clamping of the cord to allow blood to flow to the baby (unless the baby needs resuscitation).
The abdomen is palpated to assess for a uterine contraction before delivery of the placenta.
Controlled cord traction is carefully applied during uterine contractions to help deliver the placenta, stopping if there is resistance. At the same time the other hand presses the uterus upwards (in the opposite direction) to prevent uterine prolapse. The aim is to deliver the placenta in one piece.
After delivery the uterus is massaged until it is contracted and firm. The placenta is examined to ensure it is complete and no tissue remains in the uterus.
Advantage and disadvantage of active management of third stage of labour
Active management shortens the third stage and reduces the risk of bleeding, but can be associated with nausea and vomiting.
When will active management be used in third stage of labour?
Routinely offered to ALL WOMEN reduce the risk of PPH
Initiated in hemorrhage
Initiated if more than a 60-minute delay in delivery of the placenta (prolonged third stage)
What is a TENS machine
Attached to back delivers small electric pulses for pain relief in early labour
Pethidine pros and cons
Pros
Effective pain relief
Relaxing effects allows for smoother contractions
Cons
Baby may need naloxone if given too close to birth
Mother may not like numb feeling detached from contractions
Epidural side effects
Can be patchy if anesthetic fails to reach all areas
Hypotension, will require if fluids
Headache
Prolonging of second stage of labour
More likely to need assisted delivery
Entonox pros and cons
Pros
O2 good for baby
Doesn’t linger in system for long
Cons
Drowsiness light headedness
Relatively mild
When can you attempt external cephalic version for a transverse lie
You can attempt external cephalic version for a transverse lie if the amniotic sac has not ruptured
What should be assessed prior to induction of labour?
The Bishop score should be assessed in all women prior to induction of labour.
Components of bishop score?
Cervical position (posterior/intermediate/anterior)
Cervical consistency (firm/intermediate/soft)
Cervical effacement (0-30%/40-50%/60-70%/80%)
Cervical dilation (<1 cm/1-2 cm/3-4 cm/>5 cm)
Foetal station (-3/-2/-1, 0/+1,+2)
A bishop score lower than what number indicated labour is unlikely to start without induction?
5
When suspecting PPROM if there is no fluid in the posterior vaginal on vault then how might you investigate?
ultrasound may be used to look for oligohydramnios
What is required to make a diagnosis of PPROM?
History PLUS positive speculum examination (pool of fluid noted in the vagina) is required to make a diagnosis of PPROM.
Intrahepatic cholestasis of pregnancy increases the risk of stillbirth; therefore how is delivery managed?
Induction of labour is generally offered at 37-38 weeks gestation
Indications for a C section
absolute cephalopelvic disproportion
placenta praevia grades 3/4
pre-eclampsia
post-maturity
IUGR
fetal distress in labour/prolapsed cord
failure of labour to progress
malpresentations: brow
placental abruption: only if fetal distress; if dead deliver vaginally
vaginal infection e.g. active herpes
cervical cancer (disseminates cancer cells)
Category 1 C section
Most urgent
an immediate threat to the life of the mother or baby
examples indications include: suspected uterine rupture, major placental abruption, cord prolapse, fetal hypoxia or persistent fetal bradycardia
delivery of the baby should occur within 30 minutes of making the decision
Category 2 C section
Urgent but less than cat 1
maternal or fetal compromise which is not immediately life-threatening
delivery of the baby should occur within 75 minutes of making the decision
Cat 3 C section
Less urgent than Cat 1 and 2
delivery is required, but mother and baby are stable
Category 4 C section
Elective
Serious maternal complications of C Section
emergency hysterectomy
need for further surgery at a later date, including curettage (retained placental tissue)
admission to intensive care unit
thromboembolic disease
bladder injury
ureteric injury
death (1 in 12,000)
“Serious” implications of C section on future deliveries
increased risk of uterine rupture during subsequent pregnancies/deliveries
increased risk of antepartum stillbirth
increased risk in subsequent pregnancies of placenta praevia and placenta accreta)
Frequent risks of c section
Maternal
persistent wound and abdominal discomfort in the first few months after surgery
increased risk of repeat caesarean section when vaginal delivery attempted in subsequent pregnancies
readmission to hospital
haemorrhage
infection (wound, endometritis, UTI)
Fetal:
lacerations, one to two babies in every 100
When is VBAC suitable/not suitable
planned VBAC is an appropriate method of delivery for pregnant women at >= 37 weeks gestation with a single previous Caesarean delivery
around 70-75% of women in this situation have a successful vaginal delivery
contraindications include previous uterine rupture or classical (vertical) caesarean scar
What should be offered to women with a previous baby with early- or late-onset GBS disease who is in labour
Maternal intravenous antibiotic prophylaxis should be offered to women during labour with a previous baby with early- or late-onset GBS disease
Actions to take in shoulder dystocia?
Initially, request senior help and ask the mother to hyperflex their legs (also called McRobert’s manouvere) and apply suprapubic pressure. This method works in 90% of cases.
If this method fails, episiotomy is required to allow internal manouveres. A number of potential options, including Wood’s screw manouvere and grasping and manipulation of the posterior arm are then possible.
Last resorts include symphisiotomy and the Zavanelli manouvere (which includes Caesarean section, however by this point fetal damage is often irreversible)
Delivery in case of shoulder dystocia
Immediately after shoulder dystocia is recognised, additional help should be called.
Fundal pressure should not be used.
An episiotomy is not always necessary.
Induction of labour at term can actually reduce the incidence of shoulder dystocia in women with gestational diabetes.
McRoberts manoeuvre is the first line intervention as it is known to be simple, rapid and effective in most cases
How is carboprost given in PPH?
IM
Why is a hx of asthma significant in a woman with PPH?
IM carboprost should be avoided in patients with asthma as it can trigger bronchoconstriction.
Example of indications for category 1 C section
suspected uterine rupture
major placental abruption
cord prolapse
fetal hypoxia
persistent fetal bradycardia
What is the preferred method of induction of labour?
Vaginal PGE2 is the preferred method of induction of labour
The thyrotoxicosis phase of postpartum thyroiditis is generally managed with what?
Propranolol alone
What is Sheehan’s syndrome?
Sheehan’s syndrome is a complication of severe postpartum haemorrhage (PPH) in which the pituitary gland undergoes ischaemic necrosis which can manifest as hypopituitarism.
Most common sign of Sheehan’s syndrome?
lack of postpartum milk production and amenorrhoea following delivery.
How is Sheenans syndrome diagnosed?
Diagnosis of Sheehan’s is by inadequate prolactin and gonadotropin stimulation tests in patients with a history of severe PPH.
Place of birth
Home birth
Midwife lead units
Hospital birth
How often should contractions be in labour
3-4 every ten mins
How long do contractions last in labour
Around a minute
What dilation is established labour
4-6cm
Medicated pain relief in labour
Codeine
Entonox
Pethidine/meptid- IM (note pethidine crosses placenta)
Epidural
At what dilation can epidurals be put in
4cm onwards
Frequency of observations on mother in labour - low risk
4hrly
Established labour prior to full dilatation - feotal observation frequency
15 min observations with sonicade
Full dilation - how often listen to to foetal HR
every five mins
How long does the second stage of labour typically last in nulliparous women?
40 mins
Occurrence of cervical ripening in relation to hormones
It occurs in response to oestrogen, relaxin and prostaglandins breaking down cervical connective tissue; prostaglandins are of particular importance. Prostaglandins are produced by the placenta, the uterine decidua, the myometrium and the membranes. Their synthesis increases throughout the third trimester as a result of an increase in the oestrogen:progesterone ratio.
What does cervical ripening involve?
A reduction in collagen.
An increase in glycosaminoglycans.
An increase in hyaluronic acid.
Reduced aggregation of collagen fibres.
This means that the cervix offers less resistance to the presenting part of the foetus during labour.
What changes towards the end of pregnancy help to facilitate an increase in uterine musculature excitability
The relative decrease in progesterone in relation to oestrogen that occurs towards the end of pregnancy helps to facilitate an increase in the excitability of the uterine musculature. This is because progesterone typically inhibits contractions and oestrogen increases the number of gap junctions between smooth muscle cells, increasing contractility.
Mechanical stretching of the uterus also helps to increase contractility – this means as the foetus grows, the contractility of the muscle increases.
Why does oxytocin have only a limited action during most of the pregnancy
Throughout pregnancy it has limited action as there are a low number of oxytocin receptors and it is inhibited by relaxin and progesterone.
How does to role of oxytocin change around 36 weeks gestation
At around 36 weeks gestation, under the influence of oestrogen there is an increase in the number of oxytocin receptors present within the myometrium. This means the uterus begins to respond to the pulsatile release of oxytocin from the posterior pituitary gland.
What is the Ferguson reflex?
Oxytocin production is increased by afferent impulses from the cervix and vagina.
This means that contractions result in a positive feedback loop to the posterior pituitary gland to release more oxytocin, leading to stronger contractions which then drives the process of labour.
Brain stimulates PG to produce oxytocin -> oxytocin carried through blood stream to uterus -> oxytocin stimulates uterine contractions and pushes baby toward cervix -> Head of baby pushes on cervix -> nerve impulse from cervix travel to brain, which then stimulates PG to produce oxytocin again
Typical rate of active phase of second stage of labour
1cm/hr in nulliparous women and 2cm/hr in multiparous women
This phase should not normally last longer than 16 hours
Why does uterine capacity decrease during the second stage of labour, and how does this help?
The fibres of the myometrium are specially adapted to drive the process of labour as they do not fully relax following each contraction. This steadily reduces the uterine capacity, so the pressure inside becomes stronger as labour progresses and helps with expulsion of the foetus.
How are contractions made more forceful and frequent in the second stage of labour
Contractions are made more forceful and frequent by the actions of two hormones:
Prostaglandins – more intracellular calcium is released per action potential, increasing the force of contractions
Oxytocin – lowers the threshold for action potentials, increasing the frequency of contractions
How long does the second stage of labour typically last in multiparous women?
20 mins
After what duration of the active stage of labour does spontaneous delivery become increasingly unlikely?
1 hour
What happens in delivery of a baby in terms of sequence of emergence?
Once the head of the foetus reaches the perineum, it extends in order to come up and out of the pelvis.
Following delivery of the head, it rotates by 90 degrees to assist with delivery of the shoulders.
The anterior shoulder delivers first, coming under the symphysis pubis while the body flexes laterally and posteriorly to aid passage.
Following this the body flexes laterally and anteriorly to help deliver the posterior shoulder.
Once the shoulders have been delivered the rest of the body follows.
In the third stage of labour, by what mechanism is normal bleeding (>500ml) controlled?
Contraction of the uterus constricts blood vessels in the myometrium
Pressure is exerted on the placental site once it has been delivered by the walls of the contracted uterus
The normal blood clotting mechanism
What effect does mechanical stretching have on the contractility of the uterus?
Increases contractibility
First stage of labour
A faster rate of cervical dilatation until 10cm dilatation is reached. This phase should not normally last longer than 16 hours.
At which point during labour does the woman typically experience the desire to push?
The woman experiences the desire to push during the passive stage of the second stage of labour. It is at this point that uterine contractions become expulsive, rotation and flexion of the foetal head are completed, and the foetus reaches the pelvic floor, resulting in the desire to push. This typically only lasts a few minutes. During the active stage of the second stage, the woman pushes in conjunction which her contractions in order to expel the foetus.
Following an umbilical cord prolapse, what can be done to avoid compression
Following an umbilical cord prolapse, the presenting part of the fetus may be pushed back into the uterus to avoid compression
For how long should magnesium sulfate be continued following a seizure?
Magnesium treatment should continue for 24 hours after delivery or after last seizure
A history of sudden collapse occurring soon after a rupture of membranes is suggestive of what?
Amniotic fluid emboli
Management of placental abruption when the fetus is alive, <36 weeks and not showing signs of distress?
admit and administer steroids
First line investigation/examination of preterm prelabour rupture of the membranes
Careful speculum examination to look for pooling of amniotic fluid in the posterior vaginal vault is the first-line investigation for preterm prelabour rupture of the membranes
What is the most appropriate mode of delivery for a patient with a classical Caesarian scar (vertical)?
Planned caesarean section at 37 weeks gestation
Classical caesarean scar is a contraindication to vaginal birth after caesarean
Classical caesarean scar is a contraindication to vaginal birth after caesarean - why?
A vaginal delivery is contraindicated in this scenario due to the increased risk of uterine rupture which could be potentially fatal for both the mother and the baby.
Risks of prematurity?
increased mortality depends on the gestation
respiratory distress syndrome
intraventricular haemorrhage
necrotizing enterocolitis
chronic lung disease, hypothermia, feeding problems, infection, jaundice
retinopathy of prematurity
important cause of visual impairment in babies born before 32 weeks gestation
the cause is not fully understood and multivariate. One of the contributing factors is thought to be over oxygenation (e.g. during ventilation) resulting in a proliferation of retinal blood vessels (neovascularization)
screening is done in at-risk groups
hearing problems
What is complete breech presentation
Breech presentation – the legs are first. This can be:
Complete breech – with hips and knees flexed (like doing a cannonball jump into a pool)
What is footling breech presentation
Breech presentation – the legs are first. This can be:
Footling breech – with a foot hanging through the cervix
What is frank breech presentation?
Breech presentation – the legs are first. This can be:
Frank breech – with hips flexed and knees extended, bottom first
What is transverse lie?
Fetus side to side
What is longitudinal lie
Fetus straight up and down
What is oblique lie?
Fetus is at an angle
What is cephalic presentation
Head is the part of the Fetus closest to the cervix
What is shoulder presentation
Shoulder is the part of Fetus closest to the cervix
Cardinal movements of labour - 1.descent
The fetus descends into the pelvis.
In the primigravida this is likely to occur from 38 weeks gestation onwards, in a multigravida woman, this may not occur until labour is established.
Descent is encouraged by:
Increased abdominal muscle tone
Braxton hicks in the late stages of pregnancy
Fundal dominance of the uterine contractions during labour
Increased frequency and strength of contractions during labour
As the head descends, it moves towards the pelvic brim in either the left or right occipito-transverse position (this means the occiput can be facing the left side or right side of the mother’s pelvis).
Cardinal movements of labour - 2. Engagement
This is when the largest diameter of the fetal head descends into the maternal pelvis.
The term engagement is referring to the widest part of the fetal head successfully negotiating its way down deep into the maternal pelvis. Engagement is identified by abdominal palpation, where the fetal head is 3/5th palpable or less.
Feotal head reaches station 0
How much of the fetal head is palpable at engagement
3/5 or less
Cardinal movements of labour 3. Flexion
As the fetus descends through the pelvis, fundal dominance of uterine contraction exerts pressure down the fetal spine towards the occiput, forcing the occiput to come into contact with the pelvic floor. When this occurs the fetal neck flexes (chin to chest) allowing the circumference of the fetal head to reduce to sub-occipitobregmatic (9.5cm).
In this position, the fetal skull has a smaller diameter which assists passage through the pelvis.
Cardinal movements of labour - 4. Internal rotation
The pelvic floor has a gutter shape with a forward and downward slope, encouraging the fetal head to rotate from the left or right occipito-transverse position a total of 90-degrees, to an occipital-anterior (occiput facing forward) position, to lie under the subpubic arch.
With each maternal contraction, the fetal head pushes down on the pelvic floor. Following each contraction, a rebound effect supports a small degree of rotation. Regular contractions eventually lead to the fetal head completing the 90-degree turn.
This rotation will occur during established labour and it is commonly completed by the start of the second stage. Further descent leads to the fetus moving into the vaginal canal and eventually, with each contraction, the vertex becomes increasingly visible at the vulva.
Cardinal movements,emits of labour 5.extensions
The occiput slips beneath the suprapubic arch allowing the head to extend. The fetal head is now born and will be facing the maternal back with its occiput anterior.
What is crowning
When the widest diameter of the fetal head successfully negotiates through the narrowest part of the maternal bony pelvis, the fetal head is considered to be ‘crowning’. This is clinically evident when the head, visible at the vulva, no longer retreats between contractions. Complete delivery of the head is now imminent and often the woman, who has been pushing, is encouraged to pant so that the head is born with control.
6th Cardinal movement of labour - expulsion
Because the shoulders at the point of the head being delivered are only just reaching the pelvic floor they are often still negotiating the pelvic outlet and the fetus may naturally align its head with the shoulders.
This is called restitution and visually you may see the head externally rotate to face the right or left medial thigh of the mother.
During the next contraction, the shoulders, having reached the pelvic floor, will complete their rotation from a transverse position to an anterior-posterior position. Evidence of this manoeuvre happening inside can be visualised by seeing the head externally rotating as the fetus keeps its spine aligned.
Cardinal movements of labour -7. Expulsion
Downward traction by the healthcare professional will assist the delivery of the anterior shoulder below the suprapubic arch.
This is followed by upward traction assisting the delivery of the posterior shoulder.
The fetal body will be delivered by the contractions, the health professional’s role is only to assist safe negotiation of this last stage.
Risks of prematurity
increased mortality depends on the gestation
respiratory distress syndrome
intraventricular haemorrhage
necrotizing enterocolitis
chronic lung disease, hypothermia, feeding problems, infection, jaundice
retinopathy of prematurity
important cause of visual impairment in babies born before 32 weeks gestation
the cause is not fully understood and multivariate. One of the contributing factors is thought to be over oxygenation (e.g. during ventilation) resulting in a proliferation of retinal blood vessels (neovascularization)
screening is done in at-risk groups
hearing problems
False labour
Occurs in the last 4 weeks of pregnancy
Presentation: contractions felt in the lower abdomen. The contractions are irregular and occur every 20 minutes. Progressive cervical changes are absent.
When and why might early delivery be considered
Early delivery is considered when growth is static on the growth charts, or other problems are identified (e.g. abnormal Doppler results).
This reduces the risk of stillbirth. Corticosteroids are given when delivery is planned early, particularly when delivered by caesarean section.
Paediatricians should be involved at birth to help with neonatal resuscitation and management if required.
Delivery of monoamniotic twins
Monoamniotic twins require elective caesarean section at between 32 and 33 + 6 weeks.
Delivery of diamniotic twins
Aim to deliver between 37 and 37 + 6 weeks
Vaginal delivery is possible when the first baby has a cephalic presentation (head first)
Caesarean section may be required for the second baby after successful birth of the first baby
Elective caesarean is advised when the presenting twin is not cephalic presentation
Delivery in cardiac arrest
Immediate caesarean section is performed in a pregnant woman when:
There is no response after 4 minutes to CPR performed correctly
CPR continues for more than 4 minutes in a woman more than 20 weeks gestation
The aim is to deliver the baby and placenta within 5 minutes of CPR commencing.
The operation is performed at the site of the arrest, for example, in A&E resus or on the ward.
The primary reason for the immediate delivery is to improve the survival of the mother.
Delivery improves the venous return to the heart, improves cardiac output and reduces oxygen consumption.
It also helps with ventilation and chest compressions.
Delivery increases the chances of the baby surviving, although this is secondary to the survival of the mother.
Delivery in placenta praevia
Planned delivery is considered between 36 and 37 weeks gestation. It is planned early to reduce the risk of spontaneous labour and bleeding. Planned cesarean section is required with placenta praevia and low-lying placenta (<20mm from the internal os).
Depending on the position of the placenta and fetus, different incisions may be made in the skin and uterus, for example, vertical incisions. Ultrasound may be around the time of the procedure to locate the placenta.
Emergency caesarean section may be required with premature labour or antenatal bleeding.
Delivery in placenta acretta
Delivery is planned between 35 to 36 + 6 weeks gestation to reduce the risk of spontaneous labour and delivery. Antenatal steroids are given to mature the fetal lungs before delivery.
Options of c section in placenta acretta
Hysterectomy with the placenta remaining in the uterus (recommended)
Uterus preserving surgery, with resection of part of the myometrium along with the placenta
Expectant management, leaving the placenta in place to be reabsorbed over time comes with significant risks, particularly bleeding and infection.
Placenta accreta
RCOG guidelines on placenta accreta discovered during delivery
The RCOG guideline (2018) suggests that if placenta accreta is seen when opening the abdomen for an elective caesarean section, the abdomen can be closed and delivery delayed whilst specialist services are put in place. If placenta accreta is discovered after delivery of the baby, a hysterectomy is recommended.
Management of breech postion
Babies that are breech before 36 weeks often turn spontaneously, so no intervention is advised. External cephalic version (ECV) can be used at term (37 weeks) to attempt to turn the fetus.
Where ECV fails, women are given a choice between vaginal delivery and elective caesarean section. Vaginal delivery needs to involve experienced midwives and obstetricians, with access to emergency theatre if required.
Overall, vaginal birth is safer for the mother, and caesarean section is safer for the baby. There is about a 40% chance of requiring an emergency caesarean section when vaginal birth is attempted.
When the first baby in a twin pregnancy is breech, caesarean section is required.
What is external cephalic version
External cephalic version (ECV) is a technique used to attempt to turn a fetus from the breech position to a cephalic position using pressure on the pregnant abdomen. It is about 50% successful.
External cephalic version is used in babies that are breech - when?
After 36 weeks for nulliparous women (women that have not previously given birth)
After 37 weeks in women that have given birth previously
What are women given when ECV is performed
Women are given tocolysis to relax the uterus before the procedure. Tocolysis is with subcutaneous terbutaline. Terbutaline is a beta-agonist similar to salbutamol. It reduces the contractility of the myometrium, making it easier for the baby to turn.
Rhesus-D negative women require anti-D prophylaxis when ECV is performed. A Kleihauer test is used to quantify how much fetal blood is mixed with the maternal blood, to determine the dose of anti-D that is required.
Conditions increasing the risk of still birth
Unexplained (around 50%)
Pre-eclampsia
Placental abruption
Vasa praevia
Cord prolapse or wrapped around the fetal neck
Obstetric cholestasis
Diabetes
Thyroid disease
Infections, such as rubella, parvovirus and listeria
Genetic abnormalities or congenital malformations
Factors increasing the risk of still birth
Fetal growth restriction
Smoking
Alcohol
Increased maternal age
Maternal obesity
Twins
Sleeping on the back (as opposed to either side)
Still birth prevention - SGA
A risk assessment for having a baby that is small for gestational age (SGA) or with fetal growth restriction (FGR) is performed on all pregnant women. Having risk factors for SGA increases the risk of stillbirth. Those at risk have the fetal growth closely monitored with serial growth scans. This helps identify women that need further investigations and management. They may need planned early delivery when the growth is static, or other concerns are identified.
Prevention of still birth - pre eclampsia
Women at risk of pre-eclampsia are given aspirin.
Modifiable risk factors for still birth
Any modifiable risk factors for stillbirth are treated, for example, stopping smoking, avoiding alcohol and effective control of diabetes. Sleeping on the side (not the back) is advised.
Key symptoms which may cause concerns re still birth
Reduced fetal movements
Abdominal pain
Vaginal bleeding
Delivery following IUFD
Vaginal birth is first-line for most women after IUFD, unless there are other reasons for caesarean section. Women are given a choice of induction of labour or expectant management (provided immediate delivery is not required, for example with sepsis, pre-eclampsia or haemorrhage).
Expectant management involves awaiting natural labour and delivery. Women with expectant management need close monitoring. The condition of the fetus will deteriorate with time.
Induction of labour involves using a combination of oral mifepristone (anti-progesterone) and vaginal or oral misoprostol (prostaglandin analogue).
Investigating cause of still birth
With parental consent, testing is carried out after stillbirth to determine the cause:
Genetic testing of the fetus and placenta
Postmortem examination of the fetus (including xrays)
Testing for maternal and fetal infection
Testing the mother for conditions associated with stillbirth, such as diabetes, thyroid disease and thrombophilia
Identifying the cause can help reduce the risk in future pregnancies. Pregnancies are closely monitored in women with previous stillbirth.
Rupture of membranes (ROM)
The amniotic sac has ruptured
Spontaneous rupture of membranes (SROM)
Amniotic sac has ruptured spontaneously
Prelabour rupture of membranes (PROM)
The amniotic sac has ruptured before the onset of labour.
Preterm prelabour rupture of membranes (P‑PROM)
The amniotic sac has ruptured before the onset of labour and preterm (prior to 37 weeks gestation)
Prolonged rupture of membranes (also PROM)
Amniotic sac ruptures over 18 hours prior to delivery
Before what gestation is considered prematurity
37 weeks
The more premature a baby, the worse the probable outcome is considered. When is resuscitation considered in a premature birth
Babies are considered non-viable below 23 weeks gestation.
Generally, from 23 to 24 weeks, resuscitation is not considered in babies that do not show signs of life. Babies born at 23 weeks have around a 10% chance of survival.
From 24 weeks onwards, there is an increased chance of survival, and full resuscitation is offered.
Extreme preterm
Under 28 weeks
Very preterm
28-32 weeks
Moderate to late preterm
32-37 weeks
Prophylaxis for preterm labour - vaginal progesterone
Progesterone can be given vaginally via gel or pessary as prophylaxis for preterm labour.
Progesterone has a role in maintaining pregnancy and preventing labour by decreasing activity of the myometrium and preventing the cervix remodelling in preparation for delivery.
This is offered to women with a cervical length less than 25mm on vaginal ultrasound between 16 and 24 weeks gestation.
Prophylaxis of preterm labour - cervical cerclage
Cervical cerclage involves putting a stitch in the cervix to add support and keep it closed. This involves a spinal or general anaesthetic. The stitch is removed when the woman goes into labour or reaches term.
Cervical cerclage is offered to women with a cervical length less than 25mm on vaginal ultrasound between 16 and 24 weeks gestation, who have had a previous premature birth or cervical trauma (e.g. colposcopy and cone biopsy).
“Rescue” cervical cerclage may also be offered between 16 and 27 + 6 weeks when there is cervical dilatation without rupture of membranes, to prevent progression and premature delivery.
Diagnosis of preterm prelabour rupture of membranes
Rupture of membranes can be diagnosed by speculum examination revealing pooling of amniotic fluid in the vagina. No tests are required.
Where there is doubt about the diagnosis, tests can be performed:
Insulin-like growth factor-binding protein-1 (IGFBP-1) is a protein present in high concentrations in amniotic fluid, which can be tested on vaginal fluid if there is doubt about rupture of membranes
Placental alpha-microglobin-1 (PAMG-1) is a similar alternative to IGFBP-1
Management of preterm prelabour rupture of membranes
Prophylactic antibiotics should be given to prevent the development of chorioamnionitis. The NICE guidelines (2019) recommend erythromycin 250mg four times daily for ten days, or until labour is established if within ten days.
Induction of labour may be offered from 34 weeks to initiate the onset of labour.
Preterm Labour with Intact Membranes
Preterm labour with intact membranes involves regular painful contraction and cervical dilatation, without rupture of the amniotic sac.
Preterm Labour with Intact Membranes - Diagnosis
Clinical assessment includes a speculum examination to assess for cervical dilatation. The NICE guidelines (2017) recommend:
Less than 30 weeks gestation, clinical assessment alone is enough to offer management of preterm labour.
More than 30 weeks gestation, a transvaginal ultrasound can be used to assess the cervical length. When the cervical length on ultrasound is less than 15mm, management of preterm labour can be offered. A cervical length of more than 15mm indicates preterm labour is unlikely.
Fetal fibronectin is an alternative test to vaginal ultrasound. Fetal fibronectin is the “glue” between the chorion and the uterus, and is found in the vagina during labour. A result of less than 50 ng/ml is considered negative, and indicates that preterm labour is unlikely.
Improving outcomes in preterm labour without rupture of membranes
Fetal monitoring (CTG or intermittent auscultation)
Tocolysis with nifedipine: nifedipine is a calcium channel blocker that suppresses labour
Maternal corticosteroids: can be offered before 35 weeks gestation to reduce neonatal morbidity and mortality
IV magnesium sulphate: can be given before 34 weeks gestation and helps protect the baby’s brain
Delayed cord clamping or cord milking: can increase the circulating blood volume and haemoglobin in the baby at birth
What is tocolysis, and what are the options?
Tocolysis involves using medications to stop uterine contractions. Nifedipine, a calcium channel blocker, is the medication of choice for tocolysis. Atosiban is an oxytocin receptor antagonist that can be used as an alternative when nifedipine is contraindicated.
When is tocolysis used
Tocolysis can be used between 24 and 33 + 6 weeks gestation in preterm labour to delay delivery and buy time for further fetal development, administration of maternal steroids or transfer to a more specialist unit (e.g. with a neonatal ICU). It is only used as a short term measure (i.e. less than 48 hours).
Antenatal steroids
Giving the mother corticosteroids helps to develop the fetal lungs and reduce respiratory distress syndrome after delivery. They are used in women with suspected preterm labour of babies less than 36 weeks gestation.
An example regime would be two doses of intramuscular betamethasone, 24 hours apart.
Role of magnesium sulfate in preterm labour
Giving the mother IV magnesium sulfate helps protect the fetal brain during premature delivery. It reduces the risk and severity of cerebral palsy. Magnesium sulphate is given within 24 hours of delivery of preterm babies of less than 34 weeks gestation. It is given as a bolus, followed by an infusion for up to 24 hours or until birth.
Monitoring following use of magnesium sulfate in premature labour
Mothers need close monitoring for magnesium toxicity at least four hourly. This involves close monitoring of observations, as well as tendon reflexes (usually patella reflex). Key signs of toxicity are:
Reduced respiratory rate
Reduced blood pressure
Absent reflexes
Indications for induction of labour
Between 40 and 41 weeks
Prelabour rupture of membranes
Fetal growth restriction
Pre-eclampsia
Obstetric cholestasis
Existing diabetes
Intrauterine fetal death
Bishop score
The Bishop score is a scoring system used to determine whether to induce labour.
Five things are assessed and given a score based on different criteria (minimum score is 0 and maximum is 13):
Fetal station (scored 0 – 3)
Cervical position (scored 0 – 2)
Cervical dilatation (scored 0 – 3)
Cervical effacement (scored 0 – 3)
Cervical consistency (scored 0 – 2)
A score of 8 or more predicts a successful induction of labour. A score below this suggests cervical ripening may be required to prepare the cervix.
Options for induction of labour
Membrane sweep
Vaginal prostaglandin E2 (dinoprostone)
Cervical ripening ballon (CRB)
Artificial rupture of membranes with an oxytocin infusion
(Oral mifepristone (anti-progesterone) plus misoprostol are used to induce labour where intrauterine fetal death has occurred)
What is a membrane sweep and when is it performed
Membrane sweep involves inserting a finger into the cervix to stimulate the cervix and begin the process of labour.
It can be performed in antenatal clinic, and if successful, should produce the onset of labour within 48 hours.
A membrane sweep is not considered a full method of inducing labour, and is more of an assistance before full induction of labour.
It is used from 40 weeks gestation to attempt to initiate labour in women over their EDD.
Use of dinoprostone in induction of labour
Vaginal prostaglandin E2 (dinoprostone) involves inserting a gel, tablet (Prostin) or pessary (Propess) into the vagina. The pessary is similar to a tampon, and slowly releases local prostaglandins over 24 hours. This stimulates the cervix and uterus to cause the onset of labour. This is usually done in the hospital setting so that the woman can be monitored before being allowed home to await the full onset of labour.
What is a cervical ripening ballon and when is it used to induce labour
Cervical ripening balloon (CRB) is a silicone balloon that is inserted into the cervix and gently inflated to dilate the cervix. This is used as an alternative where vaginal prostaglandins are not preferred, usually in women with a previous caesarean section, where vaginal prostaglandins have failed or multiparous women (para ≥ 3).
What is artificial rupture of membranes with oxytocin infusion and when is it used
Artificial rupture of membranes with an oxytocin infusion can also be used to induce labour, although this would only be used where there are reasons not to use vaginal prostaglandins. It can be used to progress the induction of labour after vaginal prostaglandins have been used.
What are the means of monitoring during the induction of labour
Cardiotocography (CTG) to assess the fetal heart rate and uterine contractions before and during induction of labour
Bishop score before and during induction of labour to monitor the progress
Ongoing management following induction of labour when there is slow or no progress
Most women will give birth within 24 hours of the start of induction of labour.
The options when there is slow or no progress are:
Further vaginal prostaglandins
Artificial rupture of membranes and oxytocin infusion
Cervical ripening balloon (CRB)
Elective caesarean section
What is the main complication of induction of labour and what constitutes it
Uterine hyperstimulation is the main complication of induction of labour with vaginal prostaglandins. This is where the contraction of the uterus is prolonged and frequent, causing fetal distress and compromise.
The criteria for uterine hyperstimulation varies slightly between guidelines (always check local policies and involve experienced seniors). The two criteria often given are:
Individual uterine contractions lasting more than 2 minutes in duration
More than five uterine contractions every 10 minutes
Potential consequences of uterine hyperstimulation
Fetal compromise, with hypoxia and acidosis
Emergency caesarean section
Uterine rupture
Management of uterine hyperstimulation
Removing the vaginal prostaglandins, or stopping the oxytocin infusion
Tocolysis with terbutaline
What is Cardiotocography (CTG)
Cardiotocography (CTG) is used to measure the fetal heart rate and the contractions of the uterus. It is also known as electronic fetal monitoring. It is a useful way of monitoring the condition of the fetus and the activity of labour.
CTG operation
Two transducers are placed on the abdomen to get the CTG readout:
One above the fetal heart to monitor the fetal heartbeat
One near the fundus of the uterus to monitor the uterine contractions
The transducer above the fetal heart monitors the heartbeat using Doppler ultrasound. The transducer above the fundus uses ultrasound to assess the tension in the uterine wall, indicating uterine contraction.
Indications for continuous CTG monitoring in labour
Sepsis
Maternal tachycardia (> 120)
Significant meconium
Pre-eclampsia (particularly blood pressure > 160 / 110)
Fresh antepartum haemorrhage
Delay in labour
Use of oxytocin
Disproportionate maternal pain
What are the five key features on CTG
Contractions – the number of uterine contractions per 10 minutes
Baseline rate – the baseline fetal heart rate
Variability – how the fetal heart rate varies up and down around the baseline
Accelerations – periods where the fetal heart rate spikes
Decelerations – periods where the fetal heart rate drops
CTG: contractions
The number of uterine contractions per 10 minutes
Contractions are used to gauge the activity of labour.
Too few contractions indicate labour is not progressing.
Too many contractions can mean uterine hyperstimulation, which can lead to fetal compromise.
It is also important to interpret the fetal heart rate in the context of the uterine contractions.
CTG: Accelerations
Periods where fetal HR spikes
Accelerations are generally a good sign that the fetus is healthy, particularly when occurring alongside contractions of the uterus.
What is baseline rate on CTG
Baseline fetal HR
Reassuring baseline rate
110 – 160
Baseline rate - non-reassuring
100 – 109 or 161 – 180
Abnormal baseline rate
100 – 109 or 161 – 180
Variability - reassuring
5 – 25
Variability - non reassuring
Less than 5 for 30 – 50 minutes or
More than 25 for 15 – 25 minutes
Variability - abnormal
Less than 5 for over 50 minutes or
More than 25 for over 25 minutes
What is variability on CTG
Variability – how the fetal heart rate varies up and down around the baseline
What are decelerations on CTG and why are they concerning
Decelerations are a more concerning finding. The fetal heart rate drops in response to hypoxia. The fetal heart rate is slowing to conserve oxygen for the vital organs.
Decelerations – periods where the fetal heart rate drops
What are decelerations on CTG
Decelerations are a more concerning finding. The fetal heart rate drops in response to hypoxia. The fetal heart rate is slowing to conserve oxygen for the vital organs.
Where are the four types of decelerations on CTG
Early decelerations
Late decelerations
Variable decelerations
Prolonged decelerations
Early decelerations
Early decelerations are gradual dips and recoveries in heart rate that correspond with uterine contractions. The lowest point of the declaration corresponds to the peak of the contraction. Early decelerations are normal and not considered pathological. They are caused by the uterus compressing the head the fetus, stimulating the vagus nerve of the fetus, slowing the heart rate.
What causes early decelerations
They are caused by the uterus compressing the head the fetus, stimulating the vagus nerve of the fetus, slowing the heart rate.
Not normally pathological
Late decelerations on CTG
Late decelerations are gradual falls in heart rate that starts after the uterine contraction has already begun.
There is a delay between the uterine contraction and the deceleration.
The lowest point of the declaration occurs after the peak of the contraction.
What causes late decelerations on CTG
Late decelerations are caused by hypoxia in the fetus, and are a more concerning finding. They may be caused by excessive uterine contractions, maternal hypotension or maternal hypoxia.
Variable decelerations on CTG
Variable decelerations are abrupt decelerations that may be unrelated to uterine contractions. There is a fall of more than 15 bpm from the baseline. The lowest point of the declaration occurs within 30 seconds, and the deceleration lasts less than 2 minutes in total. Variable decelerations often indicate intermittent compression of the umbilical cord, causing fetal hypoxia. Brief accelerations before and after the deceleration are known as shoulders, and are a reassuring sign that the fetus is coping.
Prolonged decelerations on CTG
Prolonged decelerations last between 2 and 10 minutes with a drop of more than 15 bpm from baseline. This often indicates compression of the umbilical cord, causing fetal hypoxia. These are abnormal and concerning.
What makes a CTG reassuring
CTG is reassuring when there are no decelerations, early decelerations or less than 90 minutes of variable decelerations with no concerning features.
What makes a CTG abnormal
Regular variable decelerations and late decelerations are classed as non-reassuring or abnormal, depending on the features.
Prolonged decelerations are always abnormal.
Non reassuring CTG
Regular variable decelerations and late decelerations are classed as non-reassuring or abnormal, depending on the features.
What are the four categories of CTG and what defines them
Normal
Suspicious: a single non-reassuring feature
Pathological: two non-reassuring features or a single abnormal feature
Need for urgent intervention: acute bradycardia or prolonged deceleration of more than 3 minutes
The outcome of the CTG will guide management, such as what?
Escalating to a senior midwife and obstetrician
Further assessment for possible causes, such as uterine hyperstimulation, maternal hypotension and cord prolapse
Conservative interventions such as repositioning the mother or giving IV fluids for hypotension
Fetal scalp stimulation (an acceleration in response to stimulation is a reassuring sign)
Fetal scalp blood sampling to test for fetal acidosis
Delivery of the baby (e.g. instrumental delivery or emergency caesarean section)
The rules of 3 for fetal bradycardia when they are prolonged
3 minutes – call for help
6 minutes – move to theatre
9 minutes – prepare for delivery
12 minutes – deliver the baby (by 15 minutes)
What is a sinusoidal CTG, what does it indicate
A sinusoidal CTG is a rare pattern to be aware of, as it can indicate severe fetal compromise. It gives a pattern similar to a sine wave, with smooth regular waves up and down that have an amplitude of 5 – 15 bpm. It is usually associated with severe fetal anaemia, for example, caused by vasa praevia with fetal haemorrhage.
DR C BRaVADO
DR C BRaVADO is a mnemonic often taught to assess the features of a CTG in a structured way. It involves assessing in order:
DR – Define Risk (define the risk based on the individual woman and pregnancy before assessing the CTG)
C – Contractions
BRa – Baseline Rate
V – Variability
A – Accelerations
D – Decelerations
O – Overall impression (given an overall impression of the CTG and clinical picture)
What is cord prolapse and why is it serious?
Cord prolapse is when the umbilical cord descends below the presenting part of the fetus and through the cervix into the vagina, after rupture of the fetal membranes.
There is a significant danger of the presenting part compressing the cord, resulting in fetal hypoxia.
What is the highest risk factor for cord prolapse
The most significant risk factor for cord prolapse is when the fetus is in an abnormal lie after 37 weeks gestation (i.e. unstable, transverse or oblique). Being in an abnormal lie provides space for the cord to prolapse below the presenting part. In a cephalic lie, the head typically descends into the pelvis, without room for the cord to descend.
How is umbilical cord prolapse diagnosed
Umbilical cord prolapse should be suspected where there are signs of fetal distress on the CTG. A prolapsed umbilical cord can be diagnosed by vaginal examination. Speculum examination can be used to confirm the diagnosis.
Management of cord prolapse
Emergency caesarean section is indicated where cord prolapse occurs. (A normal vaginal delivery has a high risk of cord compression and significant hypoxia to the baby)
The cord should be kept warm and wet and have minimal handling whilst waiting for delivery (handling causes vasospasm) (Pushing the cord back in is not recommended)
When the baby is compressing a prolapsed cord, the presenting part can be pushed upwards to prevent it compressing the cord.
The woman can lie in the left lateral position (with a pillow under the hip) or the knee-chest position (on all fours), using gravity to draw the fetus away from the pelvis and reduce compression on the cord.
Tocolytic medication (e.g. terbutaline) can be used to minimise contractions whilst waiting for delivery by caesarean section.
What is shoulder dystocia
Shoulder dystocia is when the anterior shoulder of the baby becomes stuck behind the pubic symphysis of the pelvis, after the head has been delivered. This requires additional obstetric manoeuvres to enable delivery of the rest of the body. Shoulder dystocia is an obstetric emergency.
What is the most common cause of shoulder dystocia
Shoulder dystocia is often caused by macrosomia secondary to gestational diabetes.
Presentation of shoulder dystocia
Shoulder dystocia presents with difficulty delivering the face and head, and obstruction in delivering the shoulders after delivery of the head.
There may be failure of restitution, where the head remains face downwards (occipito-anterior) and does not turn sideways as expected after delivery of the head.
The turtle-neck sign is where the head is delivered but then retracts back into the vagina.
Delivery techniques for shoulder dystocia
Episiotomy can be used to enlarge the vaginal opening and reduce the risk of perineal tears. It is not always necessary.
McRoberts manoeuvre involves hyperflexion of the mother at the hip (bringing her knees to her abdomen). This provides a posterior pelvic tilt, lifting the pubic symphysis up and out of the way.
Pressure to the anterior shoulder involves pressing on the suprapubic region of the abdomen. This puts pressure on the posterior aspect of the baby’s anterior shoulder, to encourage it down and under the pubic symphysis.
Rubins manoeuvre involves reaching into the vagina to put pressure on the posterior aspect of the baby’s anterior shoulder to help it move under the pubic symphysis.
Wood’s screw manoeuvre is performed during a Rubins manoeuvre. The other hand is used to reach in the vagina and put pressure on the anterior aspect of the posterior shoulder. The top shoulder is pushed forwards, and the bottom shoulder is pushed backwards, rotating the baby and helping delivery. If this does not work, the reverse motion can be tried, pushing the top shoulder backwards and the bottom shoulder forwards.
Zavanelli manoeuver involves pushing the baby’s head back into the vagina so that the baby can be delivered by emergency caesarean section.
What is Rubin’s manouever
Rubins manoeuvre involves reaching into the vagina to put pressure on the posterior aspect of the baby’s anterior shoulder to help it move under the pubic symphysis.
What is the Woods screw manoeuvre
Wood’s screw manoeuvre is performed during a Rubins manoeuvre (reaching into the vagina to put pressure on the posterior aspect of the baby’s anterior shoulder to help it move under the pubic symphysis)
The other hand is used to reach in the vagina and put pressure on the anterior aspect of the posterior shoulder.
The top shoulder is pushed forwards, and the bottom shoulder is pushed backwards, rotating the baby and helping delivery. If this does not work, the reverse motion can be tried, pushing the top shoulder backwards and the bottom shoulder forwards.
What is the Zavanelli manoeuver
involves pushing the baby’s head back into the vagina so that the baby can be delivered by emergency Caesarean section
What are the key complications of shoulder dystocia
Fetal hypoxia (and subsequent cerebral palsy)
Brachial plexus injury and Erb’s palsy
Perineal tears
Postpartum haemorrhage
What is meant by instrumental delivery
Instrumental delivery refers to a vagina delivery assisted by either a ventouse suction cup or forceps. Tools are used to help deliver the baby’s head. About 10% of births in the UK are assisted by an instrumental delivery.
The procedure can usually be carried out on the labour ward. However, if there are concerns about whether it will be successful, the woman may be moved to theatre so that rapid delivery by caesarean section can be performed if necessary.
What is recommended after instrumental delivery to reduce the risk of maternal infection?
A single dose of co-amoxiclav
Potential indications for instrumental delivery
Failure to progress
Fetal distress
Maternal exhaustion
Control of the head in various fetal positions
What method of analgesia increases the risk of need for instrumental delivery
Epidural
What are the increased risks to the mother during and instrumental delivery
Postpartum haemorrhage
Episiotomy
Perineal tears
Injury to the anal sphincter
Incontinence of the bladder or bowel
Nerve injury (obturator or femoral nerve)
Potential risks to fetus during instrumental delivery
Key risks
Cephalohaematoma with ventouse
Facial nerve palsy with forceps
Rare but more serious risks
Subgaleal haemorrhage (most dangerous)
Intracranial haemorrhage
Skull fracture
Spinal cord injury
What is a ventouse and what is the main complication of its use
A ventouse is essentially a suction cup on a cord. The suction cup goes on the baby’s head, and the doctor or midwife applies careful traction to the cord to help pull the baby out of the vagina.
The main complication for the baby is cephalohaematoma. This involves a collection of blood between the skull and the periosteum.
What is forceps delivery and what are the associated risk
Forceps look like large metal salad tongs. They come as two pieces of curved metal that attach together, go either side of the baby’s head and grip the head in a way that allows the doctor or midwife to apply careful traction and pull the head from the vagina.
The main complication for the baby is facial nerve palsy, with facial paralysis on one side.
Forceps delivery can leave bruises on the baby’s face. Rarely the baby can develop fat necrosis, leading to hardened lumps of fat on their cheeks. Fat necrosis resolves spontaneously over time.
Rarely an instrumental delivery may result in nerve injury for the mother. How long can this take to resolve
6-8 weeks
Rarely an instrumental delivery may result in nerve injury for the mother. Which nerves may be injured?
Femoral nerve
Obturator nerve
Rarely an instrumental delivery may result in nerve injury for the mother. What will happen in the femoral nerve is damaged?
Compression against the inguinal canal during delivery, leading to:
Weakness of knee extension
Loss of patella reflex
Numbness over the anterior thigh and medial lower leg
Rarely an instrumental delivery may result in nerve injury for the mother. What will happen in the obturator nerve is damaged?
The obturator nerve may be compressed by forceps during instrumental delivery or by the fetal head during normal delivery.
Injury causes weakness of hip adduction and rotation, and numbness of the medial thigh.
What nerves can be damaged in an unassisted vaginal birth
Obturator nerve
Lateral cutaneous nerve of the thigh
Lumbosacral plexus
Common peroneal nerve
How can the lateral cutaneous nerve be injured during childbirth and how will this present
The lateral cutaneous nerve of the thigh runs under the inguinal ligament. Prolonged flexion at the hip while in the lithotomy position can result in injury,
causing numbness of the anterolateral thigh.
How can the lumbosacral plexus be injured during childbirth and how will this present
The lumbosacral plexus may be compressed by the fetal head during the second stage of labour. Injury to this network of nerves nerve can cause foot drop and numbness of the anterolateral thigh, lower leg and foot.
How can the common peroneal nerve be injured during childbirth and how will this present
The common peroneal nerve may be compressed on the head of the fibula whilst in the lithotomy position. Injury to this nerve causes foot drop and numbness in the lateral lower leg.
What is a perineal tare
A perineal tear occurs where the external vaginal opening is too narrow to accommodate the baby. This leads to the skin and tissues in that area tearing as the baby’s head passes.
Perineal tears can range from a graze, to a large tear involving the anal sphincter (third-degree) and rectal mucosa (fourth-degree).
In which situations is perineal tare more common
First births (nulliparity)
Large babies (over 4kg)
Shoulder dystocia
Asian ethnicity
Occipito-posterior position
Instrumental deliveries
What is a first degree perineal tare
First-degree – injury limited to the frenulum of the labia minora (where they meet posteriorly) and superficial skin
What is a second degree perineal tare
Second-degree – including the perineal muscles, but not affecting the anal sphincter
Third degree perineal tare
Third-degree – including the anal sphincter, but not affecting the rectal mucosa
Fourth degree perineal tare
Fourth-degree – including the rectal mucosa
Subcategories of third degree perineal tear
Third-degree – including the anal sphincter, but not affecting the rectal mucosa
3A – less than 50% of the external anal sphincter affected
3B – more than 50% of the external anal sphincter affected
3C – external and internal anal sphincter affected
Repair of pernieal tear
First-degree tears usually do not require any sutures.
When a perineal tear larger than first degree occurs, the mother usually requires sutures to correct the injury.
A third or fourth-degree tear is likely to need repairing in theatre.
Additional management measures to prevent complications following perineal tare repair
Broad-spectrum antibiotics to reduce the risk of infection
Laxatives to reduce the risk of constipation and wound dehiscence
Physiotherapy to reduce the risk and severity of incontinence
Followup to monitor for longstanding complications
When might a c section be indicated following a perineal tear
Women that are symptomatic after third or fourth-degree tears are offered an elective caesarean section in subsequent pregnancies.
Short term complications of perineal tear
Pain
Infection
Bleeding
Wound dehiscence or wound breakdown
Perineal tear long term complications
Urinary incontinence
Anal incontinence and altered bowel habit (third and fourth-degree tears)
Fistula between the vagina and bowel (rare)
Sexual dysfunction and dyspareunia (painful sex)
Psychological and mental health consequences
What is an episiotomy and why might it be done
An episiotomy is where the obstetrician or midwife cuts the perineum before the baby is delivered.
This is done in anticipation of needing additional room for delivery of the baby (e.g. before forceps delivery).
It is performed under local anaesthetic. A cut is made at around 45 degrees diagonally, from the opening of the vagina downwards and laterally, to avoid damaging the anal sphincter. This is called a mediolateral episiotomy. The cut is sutured after delivery.
What can be done to reduce the risk of perineal tear
Perineal massage is a method for reducing the risk of perineal tears. It involves massaging the skin and tissues between the vagina and anus (perineum). This is done in a structured way from 34 weeks onwards to stretch and prepare the tissues for delivery.
When during the first stage of labour would be considered delayed
Less than 2cm of cervical dilatation in 4 hours
Slowing of progress in a multiparous women
Women are monitored for their progress in the first stage of labour using what?
Partogram
What is recorded on a partogram
Cervical dilatation (measured by a 4-hourly vaginal examination)
Descent of the fetal head (in relation to the ischial spines)
Maternal pulse, blood pressure, temperature and urine output
Fetal heart rate
Frequency of contractions
Status of the membranes, presence of liquor and whether the liquor is stained by blood or meconium
Drugs and fluids that have been given
What are uterine contractions measured in
Number in ten mins (e.g. 2 in 10)
There are two lines on the partogram that indicate when labour may not be progressing adequately, what are they
Alert and action
What is meant by the alert and action lines on a partogram
There are two lines on the partogram that indicate when labour may not be progressing adequately.
These are labelled “alert” and “action”.
The dilation of the cervix is plotted against the duration of labour (time).
When it takes too long for the cervix to dilate, the readings will cross to the right of the alert and action lines.
Crossing the alert line is an indication for what
Amniotomy (artificial rupture of membranes) and a repeat examination in 2 hours.
What should be done when the action line is crossed on a partogram
Crossing the action line means care needs to be escalated to obstetric-led care and senior decision-makers for appropriate action.
Possible interventions when there is failure to progress in the second stage of labour
Changing positions
Encouragement
Analgesia
Oxytocin
Episiotomy
Instrumental delivery
Caesarean section
What is delay in the third stage of labour classed as?
More than 30 minutes with active management (intramuscular oxytocin and controlled cord traction)
More than 60 minutes with physiological management
What are the main options for managing failure to progress
Amniotomy, also known as artificial rupture of membranes (ARM) for women with intact membranes
Oxytocin infusion
Instrumental delivery
Caesarean section
What is used to stimulate uterine contractions in labour
Oxytocin is used first-line to stimulate uterine contractions during labour. It is started at a low rate and titrated up at intervals of at least 30 minutes as required. The aim is for 4 – 5 contractions per 10 minutes. Too few contractions will mean that labour does not progress. Too many contractions can result in fetal compromise, as the fetus does not have the opportunity to recover between contractions.
How much blood loss quantifies PPH
500ml after a vaginal delivery
1000ml after a caesarean section
Minor vs major PPH
Minor PPH – under 1000ml blood loss
Major PPH – over 1000ml blood loss
Major PPH: moderate vs severe
Moderate PPH – 1000 – 2000ml blood loss
Severe PPH – over 2000ml blood loss
Primary vs secondary PPH
Primary PPH: bleeding within 24 hours of birth
Secondary PPH: from 24 hours to 12 weeks after birth
What are the four causes of PPH
T – Tone (uterine atony – the most common cause)
T – Trauma (e.g. perineal tear)
T – Tissue (retained placenta)
T – Thrombin (bleeding disorder)
Risk factors for PPH
Previous PPH
Multiple pregnancy
Obesity
Large baby
Failure to progress in the second stage of labour
Prolonged third stage
Pre-eclampsia
Placenta accreta
Retained placenta
Instrumental delivery
General anaesthesia
Episiotomy or perineal tear
Preventative measures against PPH
Treating anaemia during the antenatal period
Giving birth with an empty bladder (a full bladder reduces uterine contraction)
Active management of the third stage (with intramuscular oxytocin in the third stage)
Intravenous tranexamic acid can be used during caesarean section (in the third stage) in higher-risk patients
What does management of PPH entail
Resuscitation with an ABCDE approach
Lie the woman flat, keep her warm and communicate with her and the partner
Insert two large-bore cannulas
Bloods for FBC, U&E and clotting screen
Group and cross match 4 units
Warmed IV fluid and blood resuscitation as required
Oxygen (regardless of saturations)
Fresh frozen plasma is used where there are clotting abnormalities or after 4 units of blood transfusion
In severe cases, activate the major haemorrhage protocol. Each hospital will have a major haemorrhage protocol, which gives rapid access to 4 units of crossmatched or O negative blood.
PPH: treatment to stop the bleeding
Mechanical:
- Rubbing the uterus through the abdomen to stimulates a uterine contraction (referred to as “rubbing up the fundus”)
- Catheterisation (bladder distention prevents uterus contractions)
Medical:
xytocin (slow injection followed by continuous infusion)
Ergometrine (intravenous or intramuscular) stimulates smooth muscle contraction (contraindicated in hypertension)
Carboprost (intramuscular) is a prostaglandin analogue and stimulates uterine contraction (caution in asthma)
Misoprostol (sublingual) is also a prostaglandin analogue and stimulates uterine contraction
Tranexamic acid (intravenous) is an antifibrinolytic that reduces bleeding
Surgical:
Intrauterine balloon tamponade – inserting an inflatable balloon into the uterus to press against the bleeding
B-Lynch suture – putting a suture around the uterus to compress it
Uterine artery ligation – ligation of one or more of the arteries supplying the uterus to reduce the blood flow
Hysterectomy is the “last resort” but will stop the bleeding and may save the woman’s life
When does secondary PPH occur
Secondary postpartum haemorrhage is where bleeding occurs from 24 hours to 12 weeks postpartum. This is more likely to be due to retained products of conception (RPOC) or infection (i.e. endometritis).
Secondary PPH - management and investigation
Investigations involve:
Ultrasound for retained products of conception
Endocervical and high vaginal swabs for infection
Management depends on the cause:
Surgical evaluation of retained products of conception
Antibiotics for infection
Two key causes of sepsis in pregnancy
Chorioamnionitis
Urinary tract infections
What is chorioamnionitis
Chorioamnionitis is an infection of the chorioamniotic membranes and amniotic fluid. Chorioamnionitis is a leading cause of maternal sepsis and a notable cause of maternal death (along with urinary tract infections). It usually occurs in later pregnancy and during labour.
Chorioamnionitis can be caused by a large variety of bacteria, including gram-positive bacteria, gram-negative bacteria and anaerobes.
Non specific signs of sepsis
Fever
Tachycardia
Raised respiratory rate (often an early sign)
Reduced oxygen saturations
Low blood pressure
Altered consciousness
Reduced urine output
Raised white blood cells on a full blood count
Evidence of fetal compromise on a CTG
Signs of chorioamnionitis
Abdominal pain
Uterine tenderness
Vaginal discharge
Non specific signs of sepsis (fever, tachycardia, hypotension, increase RR, reduced sats, altered conciousness, reduced urine output, evidence of feotal compromise on CTG)
What additional investigations can be done to help find the source of infection in maternal sepsis
Urine dipstick and culture
High vaginal swab
Throat swab
Sputum culture
Wound swab after procedures
Lumbar puncture for meningitis or encephalitis
Management of maternal sepsis
Continuous maternal and fetal monitoring is required. Depending on the condition of the mother and fetus, early delivery may be needed. Emergency caesarean section may be indicated when there is fetal distress, guided by a senior obstetrician. General anaesthesia is usually required for women with sepsis, as spinal anaesthesia is avoided.
Sepsis six
What is amniotic fluid embolism
Amniotic fluid embolisation is a rare (2 per 100,000 deliveries) but severe condition where the amniotic fluid passes into the mother’s blood. This usually occurs around labour and delivery. The amniotic fluid contains fetal tissue, causing an immune reaction from the mother. This immune reaction to cells from the foetus leads to a systemic illness. It has more similarities to anaphylaxis than venous thromboembolism. The mortality rate is around 20% or above.
What are the main risk factors for an amniotic fluid embolism
Increasing maternal age
Induction of labour
Caesarean section
Multiple pregnancy
Symptoms of amniotic fluid embolism
Shortness of breath
Hypoxia
Hypotension
Coagulopathy
Haemorrhage
Tachycardia
Confusion
Seizures
Cardiac arrest
Management of amniotic fluid embolism
The overall management of amniotic fluid embolism is supportive. There are no specific treatments.
Amniotic fluid embolism is a medical emergency – get help immediately. It requires the input of experienced obstetricians, medics, anaesthetics, intensive care teams and haematologists. They are likely to need transfer to the intensive care unit.
The initial management of any acutely unwell patient is with an ABCDE approach, assessing and treating:
A – Airway: Secure the airway
B – Breathing: Provide oxygen for hypoxia
C – Circulation: IV fluids to treat hypotension and blood transfusion in haemorrhage
D – Disability: Treat seizures and consider other neurological deficits
E – Exposure
Cardiopulmonary resuscitation and immediate caesarean section are required if cardiac arrest occurs.
What is uterine rupture
Uterine rupture is a complication of labour, where the muscle layer of the uterus (myometrium) ruptures. With an incomplete rupture, or uterine dehiscence, the uterine serosa (perimetrium) surrounding the uterus remains intact. With a complete rupture, the serosa ruptures along with the myometrium, and the contents of the uterus are released into the peritoneal cavity.
Uterine rupture leads to significant bleeding. The baby may be released from the uterus into the peritoneal cavity. It has a high morbidity and mortality for both the baby and mother.
Risk factors for uterine rupture
Previous C section
Vaginal birth after caesarean (VBAC)
Previous uterine surgery
Increased BMI
High parity
Increased age
Induction of labour
Use of oxytocin to stimulate contractions
What is the main risk factor for uterine rupture and why?
The main risk factor for uterine rupture is a previous caesarean section. The scar on the uterus becomes a point of weakness, and may rupture with excessive pressure (e.g. excessive stimulation by oxytocin). It is extremely rare for uterine rupture to occur in a patient that is giving birth for the first time.
How does uterine rupture present
Uterine rupture presents with an acutely unwell mother and abnormal CTG. It may occur with induction or augmentation of labour, with signs and symptoms of:
Abdominal pain
Vaginal bleeding
Ceasing of uterine contractions
Hypotension
Tachycardia
Collapse
How is uterine rupture managed
Uterine rupture is an obstetric emergency. Resuscitation and transfusion may be required. Emergency caesarean section is necessary to remove the baby, stop any bleeding and repair or remove the uterus (hysterectomy).
What is uterine inversion
Uterine inversion is a rare complication of birth, where the fundus of the uterus drops down through the uterine cavity and cervix, turning the uterus inside out. It is a very rare occurrence. It is a life-threatening obstetric emergency.
Complete vs incomplete uterine inversion
Incomplete uterine inversion (partial inversion) is where the fundus descends inside the uterus or vagina, but not as far as the introitus (opening of the vagina).
Complete uterine inversion involves the uterus descending through the vagina to the introitus.
When might uterine inversion occur
Uterine inversion may be there result of pulling too hard on the umbilical cord during active management of the third stage of labour.
How does uterine inversion present
Uterine inversion typically presents with a large postpartum haemorrhage. There may be maternal shock or collapse.
An incomplete uterine inversion may be felt with manual vaginal examination. With a complete uterine inversion, the uterus may be seen at the introitus of the vagina.
What are the three methods of treating uterine inversion
Johnson manoeuvre
Hydrostatic methods
Surgery
What is the Johnson manouever
Initial management of an inverted uterus is with the Johnson manoeuvre, which involves using a hand to push the fundus back up into the abdomen and the correct position. The whole hand and most of the forearm will be inserted into the vagina to return the fundus to the correct position. It is held in place for several minutes, and medications are used to create a uterine contraction (i.e. oxytocin). The ligaments and uterus need to generate enough tension to remain in place.
Hydrostatic methods of managing uterine inversion
Where the Johnson manoeuvre fails, hydrostatic methods can be used. This involves filling the vagina with fluid to “inflate” the uterus back to the normal position. It requires a tight seal at the entrance of the vagina, which can be challenging to achieve.
Surgical management of uterine inversion
Used when Johnson manouever and hydrostatic methods have failed
A laparotomy is performed (opening the abdomen) and the uterus is returned to the normal position.
What are the indications for an elective Caesarian section
Previous caesarean
Symptomatic after a previous significant perineal tear
Placenta praevia
Vasa praevia
Breech presentation
Multiple pregnancy
Uncontrolled HIV infection
Cervical cancer
When are elective c sections normally performed
after 39 weeks
What are the two possible incisions made in a c section
Pfannenstiel incision is a curved incision two fingers width above the pubic symphysis
Joel-cohen incision is a straight incision that is slightly higher (this is the recommended incision)
A vertical incision down the middle of the abdomen is also possible, but this is rarely used. It may be used in certain circumstances, such as when?
very premature deliveries and anterior placenta praevia.
Dissection in c section
Blunt dissection is used, after the initial incision with a scalpel, to separate the remaining layers of the abdominal wall and uterus. Blunt dissection involves using fingers, blunt instruments and traction to tear the tissues apart, rather than to cut them with sharp tools such as a scalpel. This results in less bleeding, shorter operating times and less risk of injury to the baby.
What layers are dissected during a c section
Skin
Subcutaneous tissue
Fascia / rectus sheath (the aponeurosis of the transversus abdominis and external and internal oblique muscles)
Rectus abdominis muscles (separated vertically)
Peritoneum
Vesicouterine peritoneum (and bladder) – the bladder is separated from the uterus with a bladder flap
Uterus (perimetrium, myometrium and endometrium)
Amniotic sac
What happens following dissection of relevant layers in a c section
The baby is delivered by hand with the assistance of pressure on the fundus. Forceps may be used if necessary.
The uterus is closed inside the abdomen using two layers of sutures. Exteriorisation (taking the uterus out of the abdomen) is avoided if possible. The abdomen and skin are then closed.
What risks are associated with having anaesthetic
Allergic reactions or anaphylaxis
Hypotension
Headache
Urinary retention
Nerve damage (spinal anaesthetic)
Haematoma (spinal anaesthetic)
Sore throat (general anaesthetic)
Damage to the teeth or mouth (general anaesthetic)
What anaesthetic is usually used in c section and what are the pros and cons
A spinal anaesthetic involves giving an injection of a local anaesthetic (such as lidocaine) into the cerebrospinal fluid at the lower back. This blocks the nerves from the abdomen downwards.
A spinal anaesthetic is safer, and leads to fewer complications and a faster recovery than a general anaesthetic. The potential problems are that the patient remains awake (most patients tolerate this well, but some prefer to be asleep), and it takes longer to initiate than a general anaesthetic.
What measures are taken to reduce risks prior to a c section
H2 receptor antagonists (e.g. ranitidine) or proton pump inhibitors (e.g. omeprazole) before the procedure
Prophylactic antibiotics during the procedure to reduce the risk of infection
Oxytocin during the procedure to reduce the risk of postpartum haemorrhage
Venous thromboembolism (VTE) prophylaxis with low molecular weight heparin
During a c section, why are H2 receptor antagonists (e.g. ranitidine) or proton pump inhibitors (e.g. omeprazole) given before the procedure
There is a risk of aspiration pneumonitis during caesarean section, caused by acid reflux and aspiration during the prolonged period lying flat. H2 receptor antagonists (e.g. ranitidine) or proton pump inhibitors (e.g. omeprazole) are given before the procedure to reduce the risk of this happening.
C section risks - general surgical
Bleeding
Infection
Pain
Venous thromboembolism
C section risks - complications in the post partum period
Postpartum haemorrhage
Wound infection
Wound dehiscence
Endometritis
Risks of c section - damage to local structures
Ureter
Bladder
Bowel
Blood vessels
C section risk - effect on abdominal organs
Ileus
Adhesions
Hernias
C sections - risk to future pregnancies
Increased risk of repeat caesarean
Increased risk of uterine rupture
Increased risk of placenta praevia
Increased risk of stillbirth
Risk of c section - effects on the baby
Risk of lacerations (about 2%)
Increased incidence of transient tachypnoea of the newborn
VBAC contraindications
Previous uterine rupture
Classical caesarean scar (a vertical incision)
Other usual contraindications to vaginal delivery (e.g. placenta praevia)
What type of incision is this
Pfannenstiel incision is a curved incision two fingers width above the pubic symphysis
What type of incision is this
Joel-cohen incision is a straight incision that is slightly higher (this is the recommended incision)
Requirements for forceps delivery
The requirements for instrumental delivery can be easily remembered by the mnemonic FORCEPS:
Fully dilated cervix generally the second stage of labour must have been reached
OA position preferably OP delivery is possible with Keillands forceps and ventouse. The position of the head must be known as incorrect placement of forceps or ventouse could lead to maternal or fetal trauma and failure
Ruptured Membranes
Cephalic presentation
Engaged presenting part i.e. head at or below ischial spines the head must not be palpable abdominally
Pain relief
Sphincter (bladder) empty this will usually require catheterization
Common cause of cord prolapse
ARound 50% of cord prolapse occurs after artificial rupture of membranes
Prevention of vertical transmission of HIV
The mother’s viral load will determine the mode of delivery:
Normal vaginal delivery is recommended for women with a viral load < 50 copies / ml
Caesarean section is considered in patients with > 50 copies copies / ml and in all women with > 400 copies / ml
IV zidovudine should be given during the caesarean if the viral load is unknown or there are > 10000 copies / ml
Prophylaxis treatment may be given to the baby, depending on the mothers viral load:
Low-risk babies, where the mother’s viral load is < 50 copies per ml, are given zidovudine for four weeks
High-risk babies, where the mother’s viral load is > 50 copies / ml, are given zidovudine, lamivudine and nevirapine for four weeks
What is a ‘pre-terminal’ CTG and what does it indicate?
A terminal bradycardia is when the baseline fetal heart rate drops to below 100 beats per minute for more than 10 minutes. A terminal deceleration is when the heart rate drops and does not recover for more than 3 minutes. These make up a ‘pre-terminal’ CTG and are indicators for Emergency Caesarean section.
How much and for how long is a deceleration on CTG
15 beats or more for at least 15 seconds
Labour of OP position
The fetal head may rotate spontaneously to an OA position
Delivery is possible in the OP position, however labour is likely to be longer and more painful.
Augmentation should be used if progress is slow.
Kielland’s forceps are associated with the most successful outcomes, however require particular expertise.
Generally, women will experience an earlier urge to push in OP than OA.
Which additional measure can aid the effectiveness of the McRoberts manoeuvre?
Applying suprapubic pressure
Firstline management of primary PPH secondary to uterine atony
5U of IV Syntocinon (oxytocin), followed by 0.5 mg of ergometrine.
Management of late decelerations on CTG
Late decelerations on CTG are a pathological finding and urgent fetal blood sampling is needed to assess for fetal hypoxia and acidosis. A pH of >7.2 in labour is considered normal. Urgent delivery should be considered if there is fetal acidosis.
Management of placental abruption when the fetus is alive, <36 weeks and not showing signs of distress is what?
admit and administer steroids
Normal fetal HR range on CTG
100-160
What is the main complication of induction of labour?
Uterine hyperstimulation
Risk factors for placental abruption - MMM
Muliparity
Maternal trauma
Maternal age advanced
Women with pyrexia >38 degrees during labour should be given what and why
benzylpenicillin as GBS prophylaxis
Important differential in women with preterm-PROM with a triad of maternal pyrexia, maternal tachycardia, and fetal tachycardia
chorioamnionitis
3rd vs 4th degree perineal tare
Both involve injury to the perineum involving the anal sphincter complex
4th also involves anal epitheilium/rectal mucosa
Following an ABC approach, initial steps to manage a postpartum haemorrhage include what?
Following an ABC approach, initial steps to manage a postpartum haemorrhage include palpating the uterine fundus and catheterising the patient
Cervical dilation of greater than how much is a contraindication to tocolysis
4cm
Tocolysis is contraindicated in pregnancies of greater than how many weeks gestation?
34
During a lower segment Caesarian section, what layers must be cut through to reach the feuts
SD ART EPU
Skin
Superficial fascia
Deep fascia
Anterior rectus sheath
Rectus abominus muscle
Transversalis fascia
Extraperiotneal connective tissue
Peritoneum
Uterus
Concenrs with use of MgSO4 in pre eclamspia
Magnesium sulphate - monitor reflexes + respiratory rate
Give calcium gluconate if problems
