Labour , Preterm & CS Flashcards
What are the 3 stages of labour?
- First Stage - onset defined by progressive contractions and cervical changes
a. Latent first stage - effacement (thinning) of cervix, dilatation to 3cm
b. Active first stage - dilatation from 3 - 10cm (i.e. fully dilated) - Second stage - from full dilation to delivery of the baby
a. Passive second stage - head descends down pelvis
b. Active second stage - mother bears down - Third stage - from delivery of baby to delivery of placenta and membranes
- Should occur within 30 minutes of delivery of the baby
- Can be physiological (i.e. no intervention) or actively managed (oxytocin
injection after delivery of anterior shoulder).
What is myometrial activation?
uterine contractions become synchronised and coordinated at term
What are the 3 stages of myometrial activation?
- Endocrine cascade triggered by foetus leads to increased maternal oestrogen and decreased
progesterone. Other contributing factors include uterine stretch, cortisol and the Ferguson reflex. - This leads to expression of CAPs (contraction-associated proteins) and increased production of oxytocin
and prostaglandins. - CAPs increase expression of oxytocin receptors, prostaglandin receptors, gap junction proteins and ion
channels to facilitate contractions.
- This is heavily simplified - the idea is that both agonists and receptors are increased to initiate labour.
What are the 7 levels of the second stage of labour?
- Descent - the baby’s head (providing it is in cephalic presentation) descends deeper into
the pelvis until it is no longer palpable on abdominal examination. - Flexion - the baby’s head flexes (chin to chest) to give the narrowest
(suboccipitobregmatic) diameter. - Internal rotation - baby’s occiput rotates anteriorly from the lateral position to give the
normal occipito-anterior position.
The Peer Teaching Society is not liable for any false or misleading information. 21 - Extension - baby’s occiput contacts the maternal pubic rami - it then extends and
crowns - Restitution - baby’s occiput re-aligns with its shoulders, which lie in between the
anterior-posterior and lateral positions - External rotation - baby’s shoulders rotate into anterior-posterior position (i.e.
perpendicular to mother’s). At this point, the baby’s head is delivered - it is aligned with
its shoulders, so the face looks laterally at the mother’s thigh. - Delivery of shoulders - the anterior shoulder is delivered first from beneath the pubic
ramus; the head is then gently lifted anteriorly to deliver the posterior shoulder. The rest
of the baby’s body rapidly follows.
When monitoring labour, what do we do for the initial assessment?
Initial Assessment:
- Take a history, assess for risk factors, assess for pain.
- Pulse, blood pressure, respiratory rate, urinalysis
- Abdominal palpation to determine lie, presentation, engagement, contraction strength.
- Vaginal examination to determine station, position, cervical effacement and dilatation,
presence or absence of membranes, caput or cranial moulding.
Where is progression of labour, foetal and maternal well being recorded on?
Partogram
What are the measurements of a partogram?
- Progress: cervical dilatation, descent, contractions (frequency and duration)
- Foetal wellbeing: heart rate*, amniotic fluid (liquor)
- Maternal wellbeing: pulse, blood pressure, temperature, urinalysis
How can HR be monitored in babies?
Heart rate can be monitored by intermittent auscultation with a Doppler probe (in low risk
deliveries) or continuously with a cardiotocograph (CTG, in higher risk deliveries).
How are CTG readouts interpreted?
- Normal: no non-reassuring features
- Suspicious: one non-reassuring feature
- Pathological: two non-reassuring features or one abnormal features
What are reassuring features of the CTG?
- Baseline heart rate: 110-160
- Decelerations (drops of 15 bpm for 15s): absent
- Accelerations (increases of 15 bpm for 15s): present
- Baseline variability: 5-25 bpm
What are some non-reassuring features features of the CTG?
- Baseline heart rate: 100-109 / +20
from start of
labour - Decelerations (drops of 15 bpm for 15s): Repetitive variable for
<30 mins / variable for
<30 mins / repetitive late
for 30 mins - Accelerations (increases of 15 bpm for 15s): absent
- Baseline variability: <5 for 30-50 mins />25 for <10 mins
What are some abnormal features of a CTG?
- Baseline heart rate: <100 / >160
- Decelerations (drops of 15 bpm for 15s): Repetitive variable with
concerning
characteristics >30 mins /
repetitive late >30 mins /
3 min bradycardia - Accelerations (increases of 15 bpm for 15s): absent
- Baseline variability: <5 for 50 mins / >25
for >10 mins /
sinusoidal pattern
How are some ways to cause analgesia in labour?
- Non-pharmacological: breathing and relaxation techniques / use of birthing pool
- Non-regional: Entonox (‘gas and air’ - 50:50 mix of nitrous oxide and oxygen),
intramuscular opioids e.g. diamorphine or morphine - Regional: Epidural - local anaesthetic e.g. bupivacaine combined with fentanyl bolused
into L3-4 epidural space, where it acts upon nerve roots to provide analgesia. N.B. a
‘passive hour’ without active pushing upon full dilatation is required.
What are the indications which would lead to the induction of labour?
- Prolonged pregnancy >41 weeks
- Preterm prelabour rupture of membranes (usually offered at 37+0)
- Term prelabour rupture of membranes (offer 24hrs expectant management as well)
- Maternal request
- Maternal health issues e.g. pre-eclampsia, obstetric cholestasis
- Intrauterine foetal death (IUFD) - previously
What are the methods to cause induction of labour?
- Membrane sweep: finger passed through cervix to separate part of the chorionic
membrane from the decidua; offered from 39+0. - Bishop Score <6: prostaglandin E2 pessary (dinoprostone) or osmotic dilator
- Bishop Score >6: amniotomy (artificial rupture of membranes) +/- oxytocin infusion.
What are the 3 stages of delay in labour
● First Stage: cervical dilatation of less than 2cm in 4 hours.
● Second Stage:
○ Nulliparous: >2 hour duration of second stage of labour.
○ Multiparous: >1 hour duration of second stage of labour.
● Third Stage:
○ Actively managed (oxytocin injection): >30 minutes without delivery of placenta.
○ Physiological: >60 minutes without delivery of placenta.
What are the 3 Ps of delayed labour?
Power:
- Uterine contractions - deviation from normal (i.e. 3-5 contractions of 30 seconds
duration per 10 minutes).
- Passenger:
- Size of foetus (head diameter, shoulder diameter etc.)
- Foetal presentation (cephalic: vertex, brow, face vs breech)
- Foetal position (occipito-anterior (normal), occipito-posterior, occipito-transverse)
- Passage:
- Cephalopelvic disproportion
What are the investigations for delayed labour?
● Diagnosed by regular foetal monitoring in labour.
● Aberrant foetal position can be diagnosed on vaginal examination
What is the management for 3 different stages of delayed labour?
● First Stage:
○ Membranes intact - consider amniotomy.
○ Consider oxytocin infusion - requires continuous foetal monitoring (CTG).
● Second Stage:
○ Consider oxytocin infusion.
○ Offer expedited delivery i.e. instrumental delivery or caesarean section if
vaginal delivery is improbable.
● Third Stage:
○ Controlled cord traction, IM oxytocin / ergometrine.
Officially you are preterm up to…?
36 weeks 6 days 23 hours 59 minutes and 59 seconds
Delivery prior to 37 weeks gestation:
- <28 weeks: Extremely Preterm
- 28-32 weeks: Very Preterm
- 32-37 weeks: Moderate to Late Preterm
What is the most accurate method of dating?
The most accurate method of dating is based on the measurement of a crown-rump length of a fetus on a first trimester scan.
What are the admissions for neonatal care
Approximately 10% of newborn infants require admission for neonatal care
So with 7000 babies per year at Jessops
800 come to NNU
Preterm - about 360
Term - about 240
Epidemiology of preterm birth
Approximately 10% of births globally are preterm
7.8% of births in the UK are preterm
Significant geographical variation with rates varying from 6.8% (east Asia/Oceania) to 13.2% (southern Asia) in 2020
Discrepancy in quality of data
What percentage of all births are preterm births and at what gestation age (weeks) do they happen?
0.5% = 20 -27
1% = 28-31
4.5% = 32-36
What is the background for instrumental delivery?
- AKA assisted vaginal birth (by forceps or vacuum).
- 10-15% of deliveries in the UK; ⅓ of first deliveries for nulliparous women
What are the types of instrumental delivery?
● Forceps delivery:
○ Interlocking blades fit around the baby’s head and guide it down the birth canal,
typically alongside medio-lateral episiotomy.
● Vacuum delivery:
○ Suction cup adheres to the baby’s head to assist with delivery.
What are the assisted vaginal birth classifications?
- Outlet - visible foetal scalp, skull has reached perineum, rotation less than 45 degrees.
- Low Cavity - station +2cm but not reaching perineum.
- Mid Cavity - less than 1/5th palpable abdominally, station +1 to 0cm
What are the rotational instruments used for an instrumental delivery?
- Kjelland’s forceps
- Posterior cup e.g. Kiwi
What are the non-rotational instruments for instrumental delivery?
- Neville Barnes forceps (low-cavity)
- Simpson’s forceps
- Wrigley forceps (outlet, also used in caesarean sections)
- Anterior cup
What are the indications for instrumental delivery?
- Suspected foetal compromise
- Delayed second stage
- Maternal exhaustion / distress
- Medical contraindication to Valsalva
What are the risks and complications of forceps delivery?
- Vaginal trauma
- Postpartum haemorrhage
- Obstetric anal sphincter injury (3rd degree tear)
- Facial / scalp laceration
What are the risks of vacuum delivery?
- Vaginal trauma
- Postpartum haemorrhage
- OASI
- Facial / scalp laceration
- Retinal haemorrhage
- Cephalohematoma
- Subgaleal haemorrhage
What are the types of obstetric injuries?
● 1st Degree Tear: skin only
● 2nd Degree Tear: perineal muscle
● 3rd Degree Tear: anal sphincter complex
○ Type A = less than 50% external AS
○ Type B = more than 50% external AS
○ Type C = internal and external AS injury
● 4th Degree: anorectal epithelium
What are the classifications of urgency for a Caesarean section (CS)?
● Category 1 - within 30 minutes of decision - immediate threat to life of woman or foetus
e.g. pathological CTG, placental abruption.
● Category 2 - within 75 minutes of decision - maternal / foetal compromise, not
immediately life-threatening but birth must be expedited.
● Category 3 - no compromise, early birth indicated.
● Category 4 - elective.
What are the indications for a CS?
- Breech presentation (resistant to external cephalic version).
- Placenta praevia
- Placenta accreta spectrum
- Maternal choice
- Emergency: foetal bradycardia, abruption, uterine rupture, cord prolapse, foetal pH <
7.20, failure of instrumental delivery.
What is the definition of a preterm labour?
● Onset of labour before 37 weeks gestation.
What is the pathophysiology of preterm labour?
● Similar mechanism to normal labour - probably due to:
○ Premature uterine stimulation
○ Premature withdrawal of pro-quiescent factors.
● Generally dictated by an inflammatory process causing prostaglandin release, such as:
1. Intrauterine infection
2. Placental ischaemia / decidual haemorrhage
3. Uterine stretch
4. Foetal / maternal stress
What does labour involve?
Labour involves a common downstream pathway of cervical remodelling, uterine activity and decidua/membrane activation.
What are the four phases of cervical remodelling?
Softening
Ripening
Dilation
Repair
What are the 2 primary mechanical functions of the cervix?
provide a strong outlet to the uterus until an appropriate gestation and then to become compliant and dilate to allow passage of the fetus.
Physiology of the cervix
Softening is a gradual process beginning in the first trimester that does not result in the loss of cervical integrity.
Ripening occurs as gestation advances, resulting in rapid increase in compliance and loss of strength.
Dilatation occurs when uterine contractions occur in the presence of a ripened cervix.
The triggers for these changes are variable, but the results are immune cell infiltration, matrix metalloproteinase activation resulting in ECM degradation, an increase in hyaluronic acid, increased hydration of the ECM, and weakening of the collagen network.
Result is of a softer, shorter and weaker structure which is able to stretch and dilate in response to uterine contractions
How can infection cause preterm labour?
25-40% of preterm birth may be due to infection
Most commonly intrauterine bacterial infections
Organisms include Ureaplasma urealyticum, streptococcus agalactiae, E. Coli, fusobacterium and Gardnerella
Pathways of intra-amniotic infection:
Ascending from vagina and cervix
Transplacental infection (haematogenous)
Retrograde seeding from peritoneal cavity through fallopian tube
Iatrogenic during invasive procedures e.g. amniocentesis
Infection triggers pro-inflammatory cytokines which can cause uterine contractility, membrane rupture and cervical ripening
How can ischaemia cause preterm labour?
Most common placental finding in those cases without infection/inflammation
Maternal or fetal vascular lesions such as failure of transformation of the myometrial segment of spiral arteries, thrombosis of spiral arteries, reduced number of fetal arterioles in villi.
Would account for both intrauterine growth restriction/pre-eclampsia and preterm birth.
How can uterine overdistension cause preterm labour?
Risk factors:
Structural uterine anomalies
Polyhydramnios
Multiple pregnancy
Stretching can induce myometrial contractility, prostaglandin release, expression of gap junction proteins and increased oxytocin receptors.
How can cervical weakness cause preterm labour?
Syndrome in which predominant feature is cervical ripening
Primary cervical disease
Congenital disorder
Surgical trauma e.g. LLETZ/cone biopsy
Interrupted structural integrity e.g. fully dilated CS, repeated cervical dilatation associated with surgical management miscarriage/termination
Secondary cervical insufficiency
50% associated with infection
What is the prophylactic treatment for preterm labour?
● Women with a history of previous preterm birth and cervical length <25mm are
offered treatment with:
○ Vaginal progesterone or
○ Cervical cerclage (suture)
What is the management of preterm labour?
● First Line: maternal corticosteroids (to aid foetal lung maturation):
○ Indicated if labour before 34 weeks
○ Offer betamethasone or dexamethasone, 2 doses 12 hours apart.
● Plus: magnesium sulphate (neuroprotection - reduces incidence of intraventricular
haemorrhage)
○ Indicated if labour before 30 weeks (can be given up to 34 weeks)
● Plus: tocolysis (suppression of contractions such as terbutaline) Beta agonists, CCB, Indomethacin
○ Offer nifedipine before 34 weeks gestation.
● Plus: term labour management and monitoring.
What is the periprem bundle?
These are the 11 evidence-based interventions that are brought together in the Periprem bundle, and which are also recommended in the RCOG, NICE and BAPM guidelines for preterm birth. These interventions are designed to reduce mortality and severe brain injury in infants born preterm.
What are the 11 evidence-based interventions of the periprem bundle?
Antenatal steroids
Caffeine
Delayed cord clamping
Early breast milk
Magneisum sulphate - reduces chance oc cerebral palsy
Interpartum anitbiotics
Volume targeted ventilation
Thermoregulation
Prophylactic Hydrocortisone
Probiotics
Place of birth
What are tocolytics?
Whilst we can’t stop labour, we can potentially delay delivery via tocolytics
This should only be done to facilitate optimization
Contraindicated in a situation where delayed birth may be harmful e.g. infection, maternal compromise, fetal compromise, haemorrhage
First line tocolytic drug nifedipine (atosiban second line)
Why are steroids important in preterm labour?
NICE recommends that steroids are offered to women in preterm labour between 24 and 34 weeks of pregnancy, and that they are considered from 22-24 weeks and from 34-36 weeks.
Steroids induce surfactant production and help with lung maturation. Steroids reduce neonatal mortality, necrotizing enterocolitis and intraventricular haemorrhage.
Steroids are given as two intramuscular injections 24 hours apart.
Their benefit is maximal when baby is delivered 24-48 hours after the second dose of steroids and benefit is lost if delivery occurs >7 days after steroids therefore timing is crucial.
How can cerebral palsy occur?
When a fetus is exposed to hypoxic-ischaemia and inflammation, the levels of neurotransmitter glutamate increase. Glutamate binds to receptors that activate Calcium influx which causes cell death. Magnesium blocks these receptors and therefore stops calcium influx and reduces brain cell death.
How does magnesium sulphate help with cerebral palsy?
It is given for 24 hours prior to delivery – initially as a 4 gram bolus and then 1 gram per hour infusion – but there is some benefit even if delivery occurs within a couple of hours. Even better, there are only two contraindications – myasthenia gravis and declined consent. And although it can make the mother feel unwell, these side effects are temporary, and there is no risk to the mother or fetus of repeated doses. So there is no problem if it is given and the clinical picture then changes meaning delivery is not imminent.
NICE recommends that this is offered to all women in established preterm labour (or where early delivery is planned) prior to 30 weeks, and considered up to 34 weeks, with studies ongoing assessing the efficacy in this group.
How do intrapartum antibiotics help with the prevention of early-onset neonatal Group B streptococcal disease
Intrapartum antibiotic prophylaxis reduces the risk of GBS sepsis by 86% and the risk of cerebral palsy by 50%! For every 10 women who received intrapartum antibiotic prophylaxis we will prevent one infant being born with GBS.
The recommendation is to offer antibiotics to all women in established preterm labour (so less than 37 weeks). The usual recommendation is intravenous benzylpenicillin, or cefuroxime or vancomycin if penicillin allergic. Optimal timing is for the mother to receive antibiotics 4 hours prior to birth, however even if they are given just prior to delivery
What is optical cord management?
Firstly, optimal cord management or delayed cord clamping. The recommendation is that we wait 60 seconds before clamping the cord at a preterm delivery and position the baby at or below the level of the placenta before clamping the cord. This reduces mortality by 25% with a number needed to treat of 20.
The key is that we need to work together to facilitate this, ensuring that temperature regulation and resuscitation can occur alongside delayed cord clamping. This may require a discussion with the neonatal team about scrubbing for a preterm CS to allow immediate assessment and resuscitation whilst delayed cord clamping is occurring.
Why is thermoregulation important?
Continuing on the theme of physiological interventions and we need to consider thermoregulation. Cold babies die. There is a 1/3 increase in mortality for every degree below normal body temperature. Additionally, hypothermia increases the risk of hypoglycemia (due to increased metabolic demand), respiratory distress (due to reduced surfactant production), necrotizing enterocolitis and intraventricular haemorrhage (due to impaired coagulation), all of which are associated with morbidity and mortality.
What are the RFs for preterm labour?
Previous preterm birth
Multiple gestations
Uterine or cervical anomalies
Maternal age under 17 or over 35
Smoking, substance abuse, or poor prenatal care
Infections (e.g., urinary tract infection, bacterial vaginosis)
Uterine overdistension (e.g., polyhydramnios, hydramnios)
Placental abnormalities (e.g., placenta previa, placental abruption)
History of a patient with possible preterm labor?
Previous preterm birth
Previous cervical cerclage
Multiple pregnancy
Previous cervical treatment (LLETZ, cone biopsy, trachelectomy)
Intrauterine adhesions
Uterine anomalies e.g. uterus didelphis, septum
Previous Caesarean Section at full dilatation
What is the clinical presentation of preterm labor?
Regular uterine contractions occurring at least every 10 minutes
Persistent low backache or pelvic pressure
Change in vaginal discharge (increase in volume or fluid leakage)
Abdominal cramping or menstrual-like pain
Cervical dilation and effacement on digital examination
What investigations do we use for preterm labor?
Transvaginal ultrasound to assess cervical length: A cervix <25 mm is associated with an increased risk of preterm birth.
Fetal fibronectin (fFN) testing: Elevated levels of fFN in vaginal secretions indicate an increased risk of preterm delivery within the next 7–14 days.
Fetal ultrasound to assess fetal well-being and amniotic fluid volume.
How can we assess for preterm labour?
Clinical assessment: Uterine activity and cervical dilatation prior to 37 weeks
If uncertainty e.g. uterine activity without cervical dilatation:
< 30 weeks: Treat as threatened preterm labour
>30 weeks:
Fetal fibronectin
Cervical length (<15mm higher chance)
QUIPP app
What is fetal fibronectin?
Fibronectin is an extracellular matrix glucoprotein localized at the maternal-fetal interface of the amniotic membranes
Should not be detectable at high levels in cervicovaginal secretions at preterm gestation and its presence is therefore associated with decidual/membrane activation
Can be measured via swab and speculum examination and gives result in 10 minutes
Causes of inaccuracies:
Recent intercourse
Recent digital vaginal examination
Lubricating gel
Vaginal bleeding
Predictive accuracy:
>99% Negative Predictive Value
What is the QUIPP algorithm
Slide 23 of pre-term birth lecture
How do we monitor the foetus?
Continuous electronic fetal monitoring to assess fetal heart rate patterns and detect signs of fetal distress.
Serial ultrasound evaluations to monitor fetal growth, amniotic fluid volume, and umbilical artery Doppler flow.
How can the MDT get involved in the multidisciplinary care?
Involves obstetricians, neonatologists, maternal-fetal medicine specialists, and nursing staff to provide comprehensive care for mother and baby.
Coordination of care with pediatric specialists for neonatal intensive care unit (NICU) admission and postnatal management.
How can we do patient education and counselling for preterm labor?
Provide information about signs and symptoms of preterm labor and when to seek medical attention.
Discuss lifestyle modifications (e.g., avoiding tobacco and alcohol, staying hydrated, reducing stress) to minimize the risk of preterm birth.
What is the epidemiology of preterm labor?
Preterm birth affects approximately 5-10% of pregnancies worldwide and is a leading cause of neonatal morbidity and mortality.
How can we assess preterm labor?
Digital cervical examination: Assess cervical dilation, effacement, and consistency.
Fetal fibronectin (fFN) test: Elevated levels indicate increased risk of preterm birth within 7-14 days.
Transvaginal ultrasound: Measurement of cervical length less than 25 mm is associated with increased risk of preterm birth.
Signs of preterm labour?
Uterine contractions
Vulval changes – oedema, labial parting
Cervical changes – softening, shortening, dilatation
Liquor draining, increased discharge
CTG changes
Maternal composition
Symptoms of preterm labour
Abdominal pain
Vaginal/pelvic pressure
Increased vaginal discharge, bleeding, watery loss
Gastrointestinal disturbance
Urinary symptoms
What are the complications of preterm labor?
Neonatal complications: Respiratory distress syndrome, intraventricular hemorrhage, necrotizing enterocolitis, and long-term neurodevelopmental impairment.
Maternal complications: Chorioamnionitis, postpartum hemorrhage, and psychological distress.
How do we prevent preterm labor?
Cervical cerclage: In women with a history of cervical insufficiency or short cervix, cervical cerclage may reduce the risk of preterm birth.
Progesterone supplementation: Administered to women with a history of preterm birth or short cervix to reduce the risk of recurrent preterm birth.
Prognosis of preterm labour?
Newborn babies born preterm have substantially higher risks of adverse outcomes compared with babies born at term. Risks of mortality and morbidity increase according to degree of prematurity.
1 in 10 of all premature babies will have a permanent disability such as lung disease, cerebral palsy, blindness or deafness. 1 in 2 of those born before 26 weeks.
1 in 7 babies born between 22 and 27 weeks will develop cerebral palsy, with the risk increasing significantly the earlier the gestation. Cerebral palsy is significant: 1/3 of those affected are unable to walk, ¼ are unable to talk or have epilepsy, 3/4 have pain and ½ have learning difficulties. The average lifetime healthcare cost is £800,000 and the cost to the individual and family is unquantifiable.
Early-onset neonatal Group B Streptococcal disease occurs at an incidence of about 2/1000 in preterm babies. Whilst this isn’t a very high number, the significance of those infections IS. Mortality is around 20-30% in preterm infants (compared to 2-3% for term babies) and they are at higher risk of cerebral palsy due to axonal damage caused by inflammation.
Further issues of preterm labour
Respiratory – asthma, bronchopulmonary dysplasia
Neurological – cerebral palsy, intraventricular haemorrhage, IQ/cognitive
Gastrointestinal – NEC, jaundice
Endocrine - hypoglycemia
Infection
Retinopathy
What happens in cervical length screening?
Cervical length can be measured using transvaginal ultrasound
Cervical length is recognized to reduce as gestation advances
A cervical length of <25mm between 16-24 weeks gestation is associated with an increased risk of preterm birth
Other features of the cervix can also be observed e.g. funnelling, cervical canal sludge, mobility of the posterior lip – but evidence base for their predictive potential is lacking
How can progesterone help with preterm labour?
Progesterone is the hormonal responsible for uterine quiescence and cervical stability
Supplementing progesterone in women with a history of previous preterm birth and in women with a short cervix has been demonstrated to reduce the risk of preterm birth
Daily vaginal suppositories
NICE recommends that progesterone is offered to women who have a history of delivery 16-34 weeks previously, or results from a cervical length scan demonstrating a cervix 25mm or less.
How can cervical cerclage help with preterm labour?
Provide mechanical support to the cervix
Demonstrated to reduce the risk of preterm birth
Indications:
History-indicated (elective) cerclage
Ultrasound-indicated cerclage
“Rescue” cerclage
Types of cerclage:
Macdonald
Shirodkar
Trans-abdominal
When is cervical cerclage used for women suspected of going into preterm labour?
History indicated cerclage is inserted electively around 11-14 weeks for women with a history of three or more previous preterm birth, or previous cerclage.
Ultrasound indicated cerclage for women with a cervical length <25mm and previous preterm birth or PPROM or history of cervical trauma.
Rescue cerclage for women who are identified to have premature cervical dilatation with exposed fetal membranes incidentally.
What is the definition of prelabour rupture of membranes (PROM) at term:
● Spontaneous rupture of membranes before the onset of labour at term (after 37 weeks
gestation).
● 60% of women with PROM go into normal labour within 24 hours.
What are the principle complications of premature rupture of membranes?
ascending infection
cord prolapse
premature labour
What are the investigations for PROM?
● Speculum examination - only if doubt as to whether membranes have ruptured.
● Otherwise a clinical diagnosis based on history.
What is the management for PROM?
● Expectant management up to 24 hours (with 4-hourly self-monitoring of temperature)
or:
● Induction of labour; also offered if labour does not start with expectant management.
● Note: previous history of group B streptococcus infection warrants immediate induction
for PROM, with intrapartum antibiotics (benzylpenicillin).
What is preterm prelabour rupture of membranes P-PROM?
● Rupture of membranes before 37 weeks without spontaneous labour
What are the investigations for P-PROM?
● First Line: speculum examination
○ Shows pooling of amniotic fluid
● If no pooled amniotic fluid seen, offer second line: insulin-like growth factor binding
protein-1 test or placental alpha microglobulin-1 test
What is the management for P-PROM?
● First Line: prophylactic antibiotics
○ PO erythromycin for 10 days / until established labour
What are the adaptations to Ex Utero Life?
Affects every system
Neurological Immunological
Cutaneous Haematological
Respiratory Endocrine
Cardiovascular Musculoskeletal
Gastrointestinal Sensory
What are the cardiovascular effects of Ex utero life?
Closure of foetal shunts, Perfusion of the lungs, Fall in pulmonary artery pressure, Increase in systemic blood pressure, Increase in cardiac output, Foetal lung fluid removed
What are the respiratory effects of Ex Utero life?
Little or no:
Surfactant: retained in type 2 pneumocytes
Alveoli: absent at 24 weeks then exponential increase towards term
Very common mode of death
Lung damage worse by: oxygen, sepsis, ventilation
What are the other effects of ex utero life?
Control of own movements, Independent hormonal responses, Thermoregulation, Feeding, Immunocompetence, Conversion to adult haemoglobin
What are the implantation, Embryo and Foetus?
Implantation
Weeks 1 to 2 following missed period
Embryo
Up to 8 to 9 weeks, by the end of this stage you are fully formed
Foetus:
From 12 to 16 weeks movements felt by Mother
All systems present and functioning to varying degrees
Each system is growing and developing further
Last 4 to 6 weeks is virtually all growth, mainly fat
What is the correlation of the incidence of Lung disease and gestational age?
As Gestational age increases the incidence of lung disease decreases
What is chronic lung disease of prematurity?
Officially needing oxygen at 36 weeks corrected age
Reduced lung volume
Reduced alveolar surface area
Diffusion defect
What are the symptoms of Chronic lung disease of prematurity?
Increased mortality
40% in Stage IV
~80% in initial illness
~20% later
Post discharge mortality ~7%
SIDS rate increased x7
Recurrent admissions
50% in the first year
20% in the second
Average of five admissions in the first two years (1-13)
What are the neurological effects of prematurity?
Still developing brain cells
Brain cells still migrating
Not made all synapses yet
Brain stem not myelinated yet
Changes in cerebral blood flow
Changes in oxygen levels
Changes in carbon dioxide levels
What is apnoea of prematurity?
Brain stem not myelinated fully until 32 to 34 weeks
Not uncommon to “forget” to breath, frequently associated with bradycardia
Made worse by sepsis
What are the treatments of apnoea of prematurity?
Physical: NCPAP, Stimulation
Drugs: Triple latte with an extra shot of expresso
That’s right CAFFIENE
Ventricular haemorrhage in preterm babies?
Around 80% of babies less than
32 weeks have a normal scan
Around 14% have small bleeds
Around 6% of babies less than
32 weeks have scans like these
What percentage of babies have cystic periventricular leukomalacia?
Around 5% of babies less than
32 weeks have scans like these
If we see an US change in Cystic PVL, shunted hydrocephalus, isolated ventriculomegaly, uncomplicated GMH-IVH, GMH alone and normal, what is the likelyhood of a major handicap?
Normal = 0-20 %
GMH alone = 0-20%
Uncomplicated GMH - IVH = 10-20%
Isolated ventriculomegaly= 20-40%
Shunted hydrocephalus = 45-65%
Cystic PVL = 80-95%
What are the outcomes of 22 to 25 weekers at 6 years?
In labour at
Normal 4 to 6%
Moderate/severe handicap 9 to 11%
Dead 65 to 75%
Admitted to neonatal unit
Normal 5 to 7%
Moderate/severe handicap 11 to 14%
Dead 55 to 62%
Discharged from neonatal unit
Normal 15 to 16%
Moderate/severe handicap 33 to 35%
Dead 1 to 2%
What are other morbidities faced by 22 to 25 weekers at 6 years old?
Increased need for special schooling
< 1000g 1000g - 1499g Term
15% 6% 1%
Increased need for learning support
< 1000g 1000g - 1499g Term
52% 37% 16%
What is the best way to feed baby?
Breast Milk
Infant benefits of breast milk
Less Infection:
Diarrhoea, Otitis media, Respiratory Syncytical Virus, Respiratory Infections, Enhanced Vaccine Response
Less immune driven/allergic disease:
Wheezing, Childhood cancer, Eczema, Hodgkin’s disease, Multiple sclerosis, Crohn’s disease, Diabetes mellitus, Enhanced immunologic developmentReduces risk of NECReduced Reduced SIDSReduced Gastroesophageal RefluxLower risk of Childhood Inguinal HerniaHigher IQBetter Cognitive Development
Maternal benefits of breast milk?
Reduces cancer risk for:
Breast, Uterine, Ovarian, Endometrial
Improved health with less:
Post partum haemorrhage, postnatal depression, Decrease insulin requirements in diabetics, Osteoporosis later in life, Less child abuse
Promotes postpartum weight lossOptimum child spacingLess food expenseLess medical expenseMore ecologicalDelays fertility
Why cant we give prems breast milk?
Pre terms cant suckle
So we support them with intravenous fluids/parental nutrition
Start small volumes of expressed breast milk
Steadily build to full feeds
Monitor growth
Suck and swallow starts from 32 to 34 weeks
What are the causes of unconjugated jaundice?
high levels cause kernicterus
Caused by: haemolysis, prematurity, sepsis, dehydration, hypothyroid, metabolic disease
High levels treated by phototherapy (blue light, 450 nm) or exchange transfusions
What are the causes of conjugated jaundice?
high levels not a worry
Caused by: prolonged parenteral nutrition, NEC, sepsis, metabolic, anatomical problems
Jaundice lasting more than 3 weeks needs investigation
How is necrotising enterocolitis reduced in infants?
Incidence reduced by feeding with breast milk
Why is sepsis more likely in pre term?
Last three months of gestation active IgG transfer
The more premature you are, the less of this you get
Cell mediated immunity is less active as well
Multiple invasive procedures
Plastic tubes not patrolled by the immune system
What organisms cause infection that cause sepsis in pre term infants?
Infection with organisms that are not normally pathogenic: Group B Strep, Pseudomonas, Coagulase negative staph
As well as with bacteria that are pathogenic
Fungal sepsis as a result of needing lots of antibiotics and poor immune function
What is retinopathy of prematurity?
Hyperoxic insult
Arrest of normal vascular growth
Fibrous ridge forms
Vascular proliferation
Retinal haemorrhages
Retinal detachment
Blindness
If high risk changes:
laser therapy
What to give parents with premature babies?
Antenatal counselling
Post delivery counselling
Prognostic counselling
Regular updates
Palliative care counselling
Bereavement counselling
What is the law around infants?
You have a duty of care to treat patients
The parents wishes are paramount
But
They cannot force you to administer therapy that you believe is ineffective
Indeed
Forcing treatment up on someone could be assault
But
As you have a duty of care you may want to treat when the parents do not wish the same
