Labour and delivery Flashcards
What is labour?
The progressive effacement and dilatation of the cervix in the presence of regular uterine contractions
What is meant by delivery?
Expulsion of the foetus and placenta
What is meant by ‘show’?
Cervical mucus plug
What is SROM?
Spontaneous rupture of membranes, can precede labour.
Breaking of water
What is ARM?
Artificial rupture of membranes, this is when we induce labour.
What is meant by gravidity and parity?
Gravidity= no. Of pregnancies including present
Parity= the state of giving birth
(The no. Of births >24 hours, >500g)
It gets complicated when the woman has twins, as this is only one gravidity but 2 parity’s
When do contractions occur in labour?
Contractions are rhythmic and occur every 3-4 minutes in early labour and 2-3 in advanced labour
What is meant by the lie of the baby and what are the types?
Relationship of the fetal long axis to that of the mother
Long, oblique, transverse
What is meant by the presentation?
This is the part of the foetus which is lowermost in the uterus, normally the head.
How can you work out the position of the baby?
Position is foetus dominator in relation to maternal pelvis
Work out the position by looking at the fontanelle, the posterior fontanelle tends to be in a v shape
The anterior is more of a diamond
When does labour normally occur?
Between 37 and 42 weeks gestation
What are the 3 stages of labour?
First stage- onset of labour (true contractions) until 10cm cervical dilatation
Second stage- 10cm dilatation until delivery of baby
Third stage- delivery of baby and placenta
What are the phases of the first stage of pregnancy?
Latent phase- from 0 to 3cm dilation of the cervix, this progresses at around 0.5cm per hour, they are irregular.
Active phase- from 3cm to 7cm dilation of the cervix, this progresses at around 1cm per hour, regular contractions
Transition phase- from 7cm to 10cm dilation of the cervix, this progresses at around 1cm per hour and there are strong and regular contractions.
What are braxton hicks contractions?
Occasional irregular contractions of the uterus (second and third trimester). They don’t indicate labour, they are temporary and irregular tightening or mild cramping in the abdomen.
What are the signs of labour?
. Show (mucus plug from the cervix)
Rupture of membranes
Regular, painful contractions
Dilating cervix on examination
The first stage is also split into first stage and second stage, what is meant by this?
Latent first stage is when there are both…
Painful contractions
Changes to the cervix, with effacement (getting thinner) and dilatation up to 4cm
Established first stage is when there are both
Regular and painful contractions
Dilatation of the cervix from 4cm onwards
What is the definition of prematurity?
It is defined as birth before 37 weeks gestation
What is meant by babies being non viable?
Babies are considered non viable below 23 wekeks gestation
When would you offer full resuscitation to a premature baby?
From 24 weeks onwards
What does the WHO classify prematurity as?
Under 28 weeks: extreme preterm
28-32 weeks: very preterm
32-37: moderate to late preterm
What prophylaxis can be given to prevent preterm labour?
Vaginal progesterone
Cervical cerclage
How does progesterone work for prophylaxis of preterm labour?
Progesterone can be given vaginalis or by a pessary, progesterone has a role in maintaining pregnancy and preventing labour by decreasing the activity of the myometrium and preventing the cervix remodelling in preparation for delivery.
What is cervical cerclage?
Involves putting a stitch in the cervix to add support and keep it closed, it involves general or spinal anaesthetic, the stitch is removed when the woman goes into labour or reaches term.
Who is a cervical cerclage offered to?
Offered to a woman with cervical length less than 25mm on vaginal US between 16 and 24 weeks who have had previous premature birth or cervical trauma (colposcopy/cone biopsy).
What is preterm prelabour rupture of membranes?
Is where the amniotic sac ruptures releasing amniotic fluid, before the onset of labour and in a preterm pregnancy (under 37 weeks gestation).
How do you diagnose preterm prelabour rupture of membranes?
Speculum examination revealing pooling of amniotic fluid in the vagina, if there is doubt then investigations can be carried out…
Insulin like growth factor binding protein 1 (IGFBP-1) is a protein present in high concentrations in amniotic fluid, can be tested on vaginal fluid.
Placental alpha micro globin 1 is similar
How should you manage preterm prelabour rupture of membranes?
Prophylactic antibiotics should be given to prevent the development of chorioamnionitis.
NICE recommends erythromycin 250mg four times daily for ten days or until the labour is established
Induction of labour may be offered from 34 weeks to initiate labour
What is preterm labour with intact membranes?
Involves regular painful contractions and dilatation without the rupture of the amniotic sac.
How do you diagnose preterm labour with intact membranes?
Speculum examination to assess for cervical dilatation, without rupture of the amniotic sac
Less than 30 weeks gestation, clinical assesment alone is enough to offer management of preterm labour
More than 30 weeks gestation, a trans vagina ultrasound can be used to assess the cervical length (if cervical length is less than 15mm then management of preterm labour can be offered, if cervical length is more than 15mm then preterm labour is unlikely)
What are the management options for preterm labour?
Fetal monitoring (CTG or intermittent auscultation)
Tocolysis with nifedipine
Maternal corticosteroids (these are offered before 35 weeks gestation to reduce neonatal morbidity and mortality)
IV mag sulfate can be given before 34 weeks 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
How do antenatal steroids work and what would an example regime be?
Giving the mother (<35 weeks gestation) can help to develop the fetal lungs and reduce respiratory distress syndrome after delivery
An example regime would be two doses of intramuscular beta methasone 24 hours apart
When and why would you give magnesium sulfate?
Given to mothers within 24 hours delivery of premature baby of less than 34 weeks gestation, it is given as a bolus, followed by an infusion for up to 24 hours or until birth.
Helps protect the fetal brain during premature delivery, it reduces the risk and severity of cerebral palsy.
Mothers who have been given IV magnesium, need close monitoring for magnesium toxicity at least four hourly, this involves observations and reflexes.
What should you look out for with magnesium toxicity?
Reduced RESP rate
Reduced blood pressure
Absent reflexes
When May induction of labour be used?
Prelabour rupture of membranes Fetal growth restriction Pre eclampsia Obstretic cholestasis Existing diabetes Intrauterine fetal death
When patients go over due date- between 41 and 42 weeks gestation
What is the bishop score?
Scoring system which is used to determine whether to proceed with induction of labour.
A score of 8 or more predicts there will be a successful induction of labour.
What is oral mifepristone and when is this used?
It is an anti progesterone and is used to induce labour where intrauterine fetal death has occurred.
What are the options for inducing labour?
Membrane sweep (finger into the cervix, to stimulate the cervix and begin the process of labour) should produce onset of labour within 48 hours.
Vaginal prostaglandin E2 (dinoprostone) involves inserting a gel, tablet, pessary into the vagina this slowly releases local prostaglandins over 24 hours, stimulates the cervix and uterus to cause the onset of labour
Cervical ripening balloon
Artificial rupture of membranes with oxytocin infusion (only used when you can’t use vaginal prostaglandins or used when vaginal prostaglandins have already initiated the process.
Oral mifepristone (anti progesterone) plus misoprostol can be used to induce labour where intrauterine fetal death has occurred.
How do you monitor during the induction of labour?
Cardiotocography (CTG) assess fetal heart rate and uterine contractions before and during the induction of labour
Bishop score before and during the induction of labour to monitor 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 an oxytocin infusion
Cervical balloon ripening
Elective Caesarean section
The main complication of induction of labour with vaginal prostaglandins is uterine hyperstimulation, what is this?
This is where the contraction of the uterus is prolonged and frequent, causing fetal distress and compromise.
What is cardiotrocography/ electronic fetal monitoring?
Useful way of monitoring the condition of the foetus and the activity of labour
CTG can help guide decision making and delivery
Where are the transducers places in the abdomen to get the CTG readout?
One above the foetal heart to monitor the foetal heartbeat
One near the Fundus of the uterus to monitor uterine contractions
The one above uses Doppler
The one below uses ultrasound
What are the indications for continuous CTG monitoring in labour?
Sepsis Maternal tachycardia (>120) Significant meconium Pre eclampsia (BP >160/110) Fresh anterpartum haemorrhage Delay in labour Use of o to in Disproportionate maternal pain
What are the key features to look for on a CTG?
Contractions
Baseline rate
Variability (how the fetal heart rate varies up and down around the baseline)
Accelerations- where the fetal heart rate spikes
Decelerations- where the fetal heart rate drops
What are good signs on CTG?
Accelerations- good sign that the foetus is healthy, particularly when occurring alongside contractions of the uterus.
Baseline rate and variability is describes as reassuring, non reassuring and abnormal.
What is a concerning findings on CTG?
Deceleration- this indicates hypoxia, the fetal heart rate is slowing to conserve oxygen for vital organs
What are early depolarisations?
Gradual dips an recoveries in heart rate which correspond with uterine contractions, the lowest point of deceleration corresponds to the peak of the contractions. Early decelerations are normal and not considered as pathological.
What are late decelerations?
Gradual falls in the heart rate which start after the uterine contractions has already begun, there is a delay between the uterine contractions and the deceleration, the lowest point of deceleration occurs after the peak of the contraction.
What are late decelerations caused by?
Caused by hypoxia in the foetus, caused by excessive uterine contractions, maternal hypotension or maternal hypoxia.
What is a reassuring baseline rate and variability on cardiotocography?
Baseline rate= 110-160
Variability= 5-25
What is oxytocin used for?
Stimulates the ripening of the cervix (softening) and contractions of the uterus during labour and delivery. It also plays a role in lactation during breastfeeding.
Why are oxytocin infusions used?
They induce labour
Progress labour
Improve the frequency and strength of uterine contractions
Prevent or treat postpartum haemorrhage
What is a brand name for oxytocin?
Syntocinon
What is ergometrine?
Stimulates smooth muscle contraction both in the uterus and blood vessels. It is useful for delivery of the placenta and to reduce postpartum bleeding. It may be used during the 3rd stage of the labour (delivery of placenta) and to treat postpartum haemorrhage.
What are the side effects of ergometribe?
Hypertension, diarrhoea, vomiting and angina
Avoid in eclampsia and only with significant caution in patients with hypertension
What is syntometrine
A combination drug containing oxytocin and ergometrine, it can be used for prevention or treatment of postpartum haemorrhage.
When are prostaglandins used in pregnancy?
Play a crucial role in menstruation and labour by stimulating the contraction of the uterine muscles. They also have a role in ripening the cervix before delivery.
What is dinoprostone?
A key prostaglandin which is prostaglandin E2 used for induction of labour, there are 3 forms…
. Vaginal pessaries (process)
. Vaginal tablets (prostin tablets)
. Vaginal gel (prostin gel)
What is misoprostol?
A prostaglandin analogue which binds to prostaglandin receptors and activates them. It is used as medical management in miscarriage to help complete the miscarriage.
What is mifepristone?
Anti progesterone medication which blocks the action of progesterone and halts the pregnancy and ripening of the cervix. It enhances the effects of prostaglandins to stimulate contraction of the uterus, it is often used alongside misoprostol for abortions and induction of labour after intrauterine fetal death.
It is not used during pregnancy with a healthy living foetus.
What is nifedipine?
Calcium channel blocker which acts to reduce smooth muscle contraction in the blood vessels and the uterus.
What are the two main uses of nifedipine?
Reduces blood pressure in hypertension and pre eclampsia
Tocolysis in premature labour, where it suppresses uterine activity and delays the onset of labour.
What is terbutaline?
Beta-2 agonist which is similar to salbutamol. It stimulates beta-2 adrenergic receptors. It acts in the smooth muscle of the uterus to suppress uterine contractions. It is used for tocolysis in uterine hyperstimulation.
(When the uterine contractions become excessive)
What is carbopost?
Synthetic prostaglandin analogue, meaning it binds to prostaglandin receptors. It stimulates uterine contraction and is given as a deep intramuscular injection in postpartum haemorrhage when ergometrine and oxytocin have been inadequate.
What is tranexamic acid?
Antifibrinolytic that reduces bleeding. It binds to fibrinogen and prevents it from converting to Plasmin (an enzyme that break down fibrin blood clots), used in the prevention and treatment of postpartum haemorrhage.
What is progress in labour influenced by?
The 3P’s…
Power (uterine contractions)
Passenger (size, presentation and position of the baby)
Passage (shape and size of the pelvis and soft tissues)
What does passenger refer to?
The four descriptions of the baby
Size- large are more difficult to deliver
Attitude- posture of the foetus
Lie- position of the foetus in relation to the mothers body (longitudinal, transverse, oblique)
Presentation- refers to the part of the foetus closest to the cervix.
What is meant by Cephalic presentation?
The head is first
What is a breech presentation?
Legs are first, this can be…
Complete breech (with hips and knee flexed
Frank reach (hips flexed, knee extended, bottom first)
Footling breech- foot hanging through the cervix
How would you manage failure to progress?
(Artificial rupture of me,Barnes (ARM) for women with intact membranes
Oxytocin infusion
Instrumental delivery
Caesarean section
What are your aims when using oxytocin infusion?
4-5 contractions per ten minutes
What is entonox?
This is gas and air, which can be used in pain relief during labour, contains a mix of NO 50% and O2 50% the woman takes deep breaths through the mouthpiece during the contractions.
What do you need to warn the woman taking entonox of?
Lightheadedness, nausea and sleepiness
What are Pethidine and diamorphine?
Opioid intramuscular injections which can help with anxiety and distress.
An epidural is when anaesthetic is given into the Subdural space, what are the options that can be given in an epidural?
Levobupivacaine or bupivacaine mixed with fentanyl
What are the adverse effects of an epidural?
Headache Hypotension Motor weakness in the legs Nerve damage Prolonged secondary stage Increased probability of instrumental delivery
When would a woman need urgent anaesthetic review after an epidural?
If they develop significant motor weakness (unable to straight leg raise) as the catheter may be incorrectly suited in the subarachnoid space.
What is umbilical cord prolapse?
When the umbilical cord descends below the presenting part of the foetus and through the cervix into the vagina, after rupture of the fetal membranes.
What are the causes behind umbilical cord prolapse?
When the foetus is in an abnormal lie after 37 weeks gestation
How can you diagnose umbilical cord prolapse?
Emergency Caesarean section
Baby can be pushed upwards to prevent it compressing the cord. The woman can lie in the left lateral position or knee- chest position.
Tocolysis medications can be used to minimise contractions whilst waiting for delivery.
What is shoulder dystocia?
Baby becomes stuck behind the pubic symphysis of the pelvis after the head has been delivered.
What is shoulder dystocia caused by?
Macrosomia secondary to gestational diabetes
How might shoulder dystocia present?
Failure of restitution (the head remains face downwards and does not turn sideways as expected after delivery of the head).
Turtle neck sign- when head is delivered and then retracts back into the vagina.
How do you manage shoulder dystocia?
Epiostomy McRoberts manoeuvre Pressure to the anterior shoulder Rubin’s manoeuvre Wood screws manoeuvre Zavanelli manoeuver
What are the key complications of shoulder dystocia ?
Fetal hypoxia
Brachial plexus injury and Erbs palsy
Perineal tears
Postpartum haemorrhage
How can a forceps delivery be carried out?
Either a ventouse suction cups or forceps.
What should be given after instrumental delivery to reduce the risk of infection?
Single dose of co amoxiclav to reduce risk of maternal infection.
Why might you do an instrumental delivery?
Failure to progress
Fetal distress
Maternal exhaustion
Control of the head in various fetal positions
What are the risks of instrumental delivery?
Postpartum haemorrhage Episiotomy Perineal tears Injury to the anal sphincter Incontinence of bladder or bowel Nerve injury (obturator or femoral nerve)
Cephalohaematoma with ventouse
Facial nerve palsy with forceps
What are the main complications of a forceps delivery?
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
What nerve injury can occur in the mother during a forceps delivery and how would they present?
Femoral- weakness of knee extension, loss of patella reflex, numbness of anterior thigh and medial lower leg.
Obturator- hip adduction and rotation and numbness of the medial thigh
How is an epiostomy performed?
Cutes the perineum before baby delivered
Performed under local anaesthetic
Cut is mediolateral and should be sutured after delivery
What can be done to reduce risk of perineal tears?
Perineal massage
What is the difference between physiological management and active management of the third stage of delivery?
Physiological management is where the midwife or doctor assist in delivering the placenta. It involves 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.
What does active management of the third stage of labour involve?
Involves an intramuscular dose of oxytocin after delivery of the baby
How much blood needs to be lost after delivery to be classified as postpartum haemorrhage?
500ml after vaginal delivery
1000ml after a Caesarean section
What can postpartum haemorrhage be defined as?
Minor PPH- under 1000ml
Major PPH- over 1000ml
Moderate- 1000-2000ml blood loss
Severe- over 2000ml blood loss
Primary- within 24 hours of birth
Secondary- from 24 hours till 12 weeks after birth
What are the four causes of postpartum haemorrhage?
The 4T’s: Tone (uterine atony) Trauma (tear) Tissue (retained placenta) Thrombin (bleeding disorder)
What are the risk factors of a postpartum haemorrhage?
Previous PPH Epiostomy Multiple pregnancy Large baby Failure to progress in 2nd stage of labour Prolonged third stage Pre eclampsia Instrumental delivery General anesthesia
What can be used to prevent postpartum haemorrhage?
Treating anaemia during antenatal period
Giving birth with an empty bladder
Active management of the 3rd stage
IV tranexamic acid can be used during the 3rd stage in higher risk patients.
How do you manage postpartum haemorrhage?
Resuscitation with an A to E approach
Lie the woman flat, keep her warm and communicate with her and her partner
Insert two large bore cannulas
Bloods for FBC, U and Es and clotting screen
Group and cross match 4 units
Warmed IV fluids and blood resuscitation a required
Oxygen
Fresh frozen plasma can be used when there are clotting abnormalities or after 4 units of a blood transfusion
In severe cases you can activate the major haemorrhage protocol (gives rapid access to 4 units of cross matched or O negative blood)
What are the mechanical treatment options to stop the bleeding?
Rubbing the uterus through the abdomen to stimulate a uterine contractions
Catheterisation (bladder distension prevents uterus contractions)
What is secondary postpartum haemorrhage and when is this more likely to occur?
Where bleeding occurs from 24 hours to 12 weeks postpartum. More likely to be due to retained products of conception or infection (endometritis).
How can you investigate secondary postpartum haemorrhage?
Ultrasound for retained products
ENDOCERVICAL and high vag swabs for infections
How do you manage secondary postpartum haemorrhage?
Evacuation of retained products of conception
ABx for infection
What are the indications for an elective caesarean?
Previous caesarean Symptomatic after a significant perineal tear Placenta praevia Vasa praevia Breech presentation Multiple pregnancy Uncontrolled HIV infection Cervical cancer
What are the four categories of an emergency Caesarean section?
Category 1- immediate threat to life of the mother or baby, decision to delivery time is 30 mins
Category 2- imminent threat
Decision to delivery time is 75 mins
Category 3- delivery is required but mother and baby are stable
Category 4- elective caesarean
What are the two possible incisions of a C section?
Pfannelstein incision- curved incision two finger width above pubic symphysis
Joel Cohen incision is a straight incision which is slightly higher
What is the pathophysiology behind premature rupture of membranes and pre-term premature rupture of membranes (P-PROM)?
Fetal membranes are made up of both the chorion and the amnion, they are strengthened by collagen and under normal circumstances become weaker at term in preparation for labour, in premature rupture of membranes and PPROM a combination of factors lead to early weakening and rupture of fetal membranes….
1) early activation- higher than normal levels of Apoptotic markers and MMPs in the amniotic fluid
2) infection- inflammatory markers (cytokines) contribute to the weakening of the fetal membranes
3) genetic predisposition
What are the risk factors for premature rupture of membranes and P-PROM?
Smoking Vag bleeding Lower genital tract infection Invasive procedures like amniocentesis Polyhydramnios Multiple pregnancy Cervical insufficiency
What are the clinical features of PPROM/premature rupture of membranes?
Broken waters- women experiencing a painless popping sensation followed by watery fluid leaking from the vagina
However symptoms can be more non specific like a wet pad
Lack of vagina discharge ‘washed clean’
What is the differential diagnosis of PPROM and premature rupture of membranes?
Urinary incontinence
Normal vaginal secretions of pregnancy
Increased sweat and moisture around the perineum
Loss of mucus plug
Increased cervical discharge (ie: with infection)
Vesicovaginal fistula
Loss of mucus plug
What are the investigations for PROM and P PROM?
Diagnosis is made by:
Maternal history of membrane rupture
Positive examination findings (speculum)
In all cases of premature membrane rupture, a high vaginal swab should be taken, it may grow group B streptococcus which would indicate antibiotics in labour or give a potential cause for PPROM (bacterial vaginosis)
Ferning test
Active PROM
Amnisure
Nitrazine testing
What is the management of PROM and P-PROM?
When the rupture of fetal membranes releases amniotic fluid, this acts to stimulate the uterus, therefore the majority of women with PROM/ P- PROM will start labour in 24-48 hours
The management depends on the gestation age
<34 weeks gestation: this is in favour of aiming for increased gestation
>36 weeks gestation: if labour doesn’t start, IOL is considered within 24-48 hours, due to infection risk
34-36 weeks gestation: IOL when steroids have been given
How do you manage a PROM/P-PROM in someone >36 weeks gestation?
Monitor for signs of clinical chorioamnionitis
Clindamycin/penicillin during labour if group B streptococcus is isolated
Watch and wait for 24 hours or consider induction of labour
IOL And delivery recommended after 24 hrs, however woman can go up to 96 hours
How do you manage someone with P-PROM and PROM at 34-36 weeks?
Monitor for chorioamnionitis and advise patient to avoid sexual intercourse as this can increase risk of ascending infection
Clindamycin or penicillin during labour if group B strep is isolated
Corticosteroids if between 34 and 34+6 weeks gestation
IOL and delivery recommended
How do you manage someone with PROM/ P-PROM if they are 24-33 weeks gestation?
Monitor for signs of clinical chorioamnionitis and advise patient to avoid sexual inter course
Prophylactic erythromycin 250mg QDS for ten days
Corticosteroids (as less than 34+6)
Aim expectant management until 34 weeks
What are the complications of PPROM and PROM?
Chorioamnionitis Oligohydramnios (can lead to lung hypoplasia in gestational age <24) Neonatal death Placental abruption Umbilical cord prolapse
