Discharge of amniotic fluid before the onset of labour, due to a leak or frank rupture of the amniotic sac.
Differential diagnosis: urinary incontinence, expulsion of the mucus plug, leucorrhoea.
– Intra-amniotic infection; suspect infection if there is maternal fever, persistent foetal tachycardia or loss of foetal heartbeat, or discoloured amniotic fluid.
Never administer a tocolytic agent, no matter what the gestational age, when intraamniotic infection is suspected.
– Pre-term birth, if the rupture occurs before 37 weeks LMP.
– For confirmation in case of doubt, perform speculum examination: look for fluid pooling in the vagina or leaking from cervical os when patient coughs.
– Look for a prolapsed cord (Chapter 5, Section 5.4).
– Look for a maternal cause (e.g. urinary tract or vaginal infection) and treat accordingly.
– Admit to inpatient department; rest and monitoring: temperature, heart rate, blood pressure, uterine contractions, foetal heart tone, and abnormal amniotic fluid (discoloured, purulent).
– Vaginal examinations: as few as possible, always with sterile gloves and only if the woman is in labour or induction of labour is planned.
– Antibiotic therapy:
- For the mother (routinely)
No infection, no labour, and rupture ≥ 12 hours:
amoxicillin PO1 : 3 g/day in 3 divided doses for 5 to 7 days
No infection, labour in progress, and rupture ≥ 12 hours:
ampicillin IV: initially 2 g, then 1 g every 4 hours during labour until the child is born, whether the patient received antibiotics beforehand or not; do not continue antibiotics postpartum.
If infection is present, with or without labour, regardless of the duration of the rupture:
ampicillin IV: 2 g every 6 hours
+ metronidazole IV: 500 mg every 8 hours
+ gentamicin IM: 3 to 5 mg/kg once daily
Continue IV administration for 48 hours after fever disappears then, change to amoxicillin + metronidazole PO to complete 10 days of treatment.
– If there are uterine contractions:
• Before 34 weeks LMP: tocolytic agent, except if there are signs of amniotic infection.
• After 34 weeks LMP, the risk of infection is greater than the risk of preterm birth: do not administer tocolytics.
– Induction of labour:
• In case of infection, induce labour immediately (Chapter 7, Section 7.3).
• If there is no infection, consider induction as of 34 weeks LMP if the due date is certain, better as of 37 weeks LMP.
– For ruptures occurring in the seventh and eighth month, transfer the mother, if possible, to a facility where the preterm infant can receive intensive care.
– Prepare the foetus for preterm birth:
After 26 weeks LMP and before 34 weeks LMP, help lung maturation with dexamethasone IM: 6 mg every 12 hours for 48 hours. In case of severe maternal infection, start antibiotic therapy prior to dexamethasone.
Do not use amoxicillin/clavulanic acid (increased incidence of necrotizing enterocolitis in neonates).