Labour and puerperium Flashcards
What is induction of labour
Start labour artificially
Needed in 20% of pregnancies
When safer to deliver baby than keep in utero
Can be to optimise maternal health
What are the indications for induction of labour
Prolonged gestation
Premature rupture of membranes
Maternal health problems
Fetal growth restriction
Intrauterine fetal death
When should induction of labour be used in prolonged gestation
Uncomplicated pregnancies, offer between 40+0 and 40+14
Prolonged gestation associated with fetal compromise and stillbirth
If mother declines induction, increased monitoring after 42 weeks
When should induction of labout be used in premature rupture of membranes
If >37 weeks
- Offer induction of labour or expectant management for 24 hours
If 34-37 weeks
- Time induction based on risk vs benefit
If < 34 weeks
- Delay induction (unless have fetal compromise)
What maternal health problems should lead to consideration for induction of labour
Hypertension
Pre-eclampsia
Diabetes
Obstetric cholestasis
What are the absolute contraindications for induction of labour
Cephalopelvic disproportion
Major placenta praevia
Vasa praevia
Cord prolapse
Transverse lie
Active primary genital herpes
Previous classical C-section
What are the relative contraindications for induction of labour
Breech presentation
Triplet(+) pregnancy
2+ previous low transverse C-sections
What are the methods of induction of labour
Vaginal prostaglandins
Amniotomy
Membrane sweep
How are vaginal prostaglandins used in the induction of labour
Primary method
Ripen cervix
Help with uterine contractions
Maximum 1 cycle per day (1 pessary, or 1 tablet/gel repeated after 6 hours)
What is amniotomy
Artificially rupture membranes using amnihook
Get release of prostaglandins, hope to start labour
Only when cervix is ripe
Can be given alongside syntocinon
Not first line (unless prostaglandins contraindicated) - risk of uterine hyperstimulation
What is a membrane sweep
Not a formal method of induction
Gloved finger through cervix, aim to separate membrane and release prostaglandins
Increases chances of spontaneous labour
Nulliparous: offer at 40 and 41 weeks
Multiparous: offer at 41 weeks
What methods of monitoring are used during induction of labour
Bishop score
CTG (if using oxytocin, use CTG throughout)
What is a Bishop score
Assessment of cervical ripening based on vaginal examination
Used before and during induction
> 7 = cervix favourable (high chance of response)
<4 = unlikely to progress naturally, will need prostaglandin induction
What are the complications of induction of labour
Failure of induction (offer more prostaglandins or C-section)
Uterine hyperstimulation (manage with tocolytic (anti-contraction) agents)
Cord prolapse
Infection
Pain (more severe than with natural labour)
Increased need for further intervention
Uterine rupture
What is operative vaginal delivery and what are the methods used
Use of instruments to aid delivery
Up to 3 pulls with one instrument, then switch to a different one
Ventouse
Forceps
How is ventouse used in operative vaginal delivery
Low risk of maternal complications
Attach cup to fetal head using vacuum, apply traction with each contraction
Electrical pump, or kiwi (used to rotate fetus)
Lower success rate, less maternal perineal injury, less pain, more cephalhematoma, more subgaleal haematoma, more fetal retinal haemorrhage
How are forceps used in operative vaginal delivery
Lower risk of fetal complications
2 blades, go around fetal had, apply traction with contractions
Higher rates of 3rd/4th degree tears, not ideal for rotation, no need for maternal effort
What are the maternal indications for operative vaginal delivery
Inadequate progress
- 2 hours of pushing in nulliparous
- 1 hour of pushing in multiparous
Exhaustion
Medical conditions where active pushing should be limited (intracranial pathology, congenital heart defects, severe hypertension)
What are the fetal indications for operative vaginal delivery
Suspected fetal compromise in 2nd stage of labour (abnormal CTG/bloods)
Clinical concern (significant antepartum haemorrhage…)
What are the absolute contraindications for operative vaginal delivery
Unengaged fetal head (singleton)
Incompletely dilated cervix (singleton)
True cephalo-pelvic disproportion
Breech and face presentation
Preterm (<34 weeks) - for ventouse
Fetus high risk of coagulation disorders - for ventouse
What are the relative contraindications for operative vaginal delivery
Non-reassuring fetal status with head above pelvic floor
Delivery of twin 2, where head has not engaged or cervix has re-formed
Prolapse of umbilical cord when cervix is fully dilated
What are the pre-requisites for instrumental delivery
Fully dilated
Ruptured membranes
Cephalic presentation
Defined fetal position
Fetal head at least at ischial spine
Empty bladder
Adequate pain relief
Adequate maternal pelvis
What are the fetal complications of operative vaginal delivery
Neonatal jaundice
Scalp lacerations
Cephalhaematoma
Subgaleal haematoma
Facial bruising
Facial nerve damage
Skull fractures
Retinal haemorrhage
What are the maternal complications of operative vaginal delivery
3rd/4th degree vaginal tears
VTE
Incontinence
PPH
Shoulder dystocia
Infection
What is premature rupture of membranes
ROM at least 1 hour before onset of labour
At >37 weeks
In 10-15% pregnancies
Minimum risk to mother and baby
What is pre-term premature rupture of membranes
Rupture of membranes at <37 weeks
2% pregnancies
High rates of maternal and fetal compromise
40% of pre-term pregnancies
What is the pathophysiology of PROM/P-PROM
Early weakening and rupture of membranes due to:
- Early activation of normal physiological process (high apoptotic markers and enzymes)
- Infection
- Genetic predisposition
What are the risk factors for PROM/P-PROM
Smoking (especially at <28 weeks)
Previous PROM/P-PROM
Vaginal bleeding during pregnancy
Lower genital tract infection
Invasive procedures (amniocentesis…)
Polyhydramnios
Multiple pregnancies
Cervical insufficiency
What are the clinical features of PROM/P-PROM
Typical history of ‘waters breaking’
Non-specific symptoms: gradual leaking, change in vaginal discharge
Fluid pooling in posterior fornix on speculum examination
Avoid digital vaginal examination until woman is in labour
What are the differential diagnoses for PROM/P-PROM
Urinary incontinence
Normal vaginal secretions of pregnancy
Increased sweat/moisture around perineum
Increased cervical discharge
Vesicovaginal fistula
Loss of mucus plug
What investigations are used in PROM/P-PROM
High vaginal swab (look for GBS)
Actim-PROM (swab to look for insulin like growth factor binding protein 1 in vaginal fluid)
Amnisure (swab to look for alpha microglobulin 1)
Nitrazine test (pH of vaginal fluid)
Ferning test (fern pattern on slides)
What is the management of PROM/P-PROM at <34 weeks
Aim to get to 34 weeks
Monitor for signs of choramnionitis
Avoid sexual intercourse
Prophylactic erythromycin for 10 days
Corticosteroids
What is the management of PROM/P-PROM at 34-36 weeks
Induce labour once steroids have been given
Monitor for signs of choramnionitis
Avoid sexual intercourse
Prophylactic erythromycin for 10 days
Penicillin during labour if GBS found
What is the management of PROM/P-PROM at >36 weeks
Induce labour within 24-48 hours
Monitor for signs of choramnionitis
Penicillin during labour if GBS found
What are the complications of PROM/P-PROM
Outcomes correlate with gestational age
Choramnionitis (inflammation of fetal membranes)
Oligohydramnios (more if <24 weeks)
Neonatal death (prematurity, sepsis, pulmonary hypoplasia)
Placental abruption
Umbilical cord prolapse
When is an emergency caesarean section used
Failure to progress
Fetal compromise
What are the categories of emergency caesarean sections
Category 1
- Immediate threat to life of mother or fetus
- Birth within 30 mins
Category 2
- Maternal/fetal compromise, not immediately life-threatening
- Birth within 60-75 mins
Category 3
- No maternal/fetal compromise, but need early delivery
What are the indications for caesarean section
Breech presentation
Malpresentation
Twins (twin 1 not cephalic)
Fetal compromise
Transmissible disease (poorly controlled HIV)
Primary genital herpes in 3rd trimester
Placenta praevia
Maternal diabetes
Previous major shoulder dystocia
Previous 3rd/4th degree tear
Maternal request
Benefits of caesarean section
Reduced risk of:
- Perianal trauma
- Pain
- Urinary/anal incontinence
- Uterovaginal prolapse
- Late stillbirth
- Early neonatal infection
What are the immediate complications of caesarean section
PPH (>1000 ml)
Wound haematoma
Intra-abdominal haemorrhage
Bladder/bowel trauma
Neonatal: transient tachypnoea of newborn, fetal lacerations
What are the intermediate complications of caesarean section
Infection (UTI, endometritis, respiratory)
VTE
What are the late complications of caesarean section
Urinary tract trauma
Subfertility
Negative psychological effects
Rupture/dehiscence of scar in next labour
Placenta praevia/accrete
Caesarean scar ectopic pregnancy
Risks and benefits of VBAC
Shorter hospital stay and recovery
Higher risk of uterine rupture
Risk of anal sphincter injury
Lower risk of maternal death
Good chances of success of future VBACs
Risk of respiratory difficulties/hypoxic ischaemic encephalopathy in neonate
Increased risk of stillbirth beyond 39 weeks
Risks and benefits of elective repeat caesarean section
Longer recovery
Small risk of uterine rupture
No risk of anal sphincter injury
Higher risk of maternal death
Subsequent pregnancies need to be caesarean
Higher risk of neonatal respiratory morbidity
Increased risk of placental problems
Increased risk of adhesions
What is uterine rupture, and what are the risk factors for it in VBAC
Full-thickness disruption of uterine muscle and overlying serosa
An obstetric emergency
Can get fetal hypoxia/large maternal haemorrhage
Risk factors in VBAC: previous C-section, induction of labour, obstruction of labour, multiple pregnancy, multiparity
How are VBAC deliveries managed
Deliver in hospital setting
Continuous CTG monitoring
Avoid induction where possible
Get guidance from seniors
After 39 weeks, recommendation is repeat C-section
What are the absolute contraindications for VBAC
Classical caesarean scar
Previous uterine rupture
Normal contraindications for vaginal birth
What are the relative contraindications for VBAC
Complex uterine scar
> 2 previous lower segment C-sections