4.9 Premature rupture of membranes


Discharge of amniotic fluid before the onset of labour, due to a leak or frank rupture of the amniotic sac.

4.9.1 Diagnosis

In case of doubt, perform speculum examination: look for fluid pooling in the vagina or leaking from cervical os when patient coughs.

Differential diagnosis: urinary incontinence, expulsion of the mucus plug, leucorrhoea.

4.9.2 Risks

– Intra uterine infection; suspect infection in case of maternal fever associated with one or more of the following signs: persistent foetal tachycardia or foetal death foul-smelling or purulent amniotic fluid, uterine contractions. Never administer a tocolytic agent, no matter what the gestational age, when intra-uterine infection is suspected.
– Prolapsed cord.
– Pre-term birth, if the rupture occurs before 37 weeks LMP.

4.9.3 Management

– In the event of preterm rupture of membranes, look for a maternal cause (e.g. urinary or genital tract infection) and treat accordingly.
– Admit to inpatient department and monitor: temperature, heart rate, blood pressure, uterine contractions, foetal heart tone, abnormal amniotic fluid (foul-smelling, 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.
– Antibiotherapy:
• For the mother:

DiagnosisTreatment

Preterm (< 37 weeks)
and
No infection and no labour

amoxicillin PO: 1 g 3 times daily for 7 days
Do not use amoxicillin/clavulanic acid (increased incidence of necrotizing enterocolitis in neonates).

Preterm (< 37 weeks)
and
No infection and labour in progress

ampicillin IV: 2 g, then 1 g every 4 hours during labour until the child is born (whether the patient received amoxicillin PO beforehand)
Do not continue antibiotics after delivery.

Term (≥ 37 weeks)
and
No infection and rupture of membranes ≥ 12 hours, whether in labour or not 

ampicillin IV: 2 g, then 1 g every 4 hours during labour until the child is born
Do not continue antibiotics after delivery.

Presence of infection whether in labour or not, regardless of the duration of the rupture

ampicillin IV: 2 g every 8 hours 
metronidazole IV: 500 mg every 8 hours 
gentamicin IM: 5 mg/kg once daily
Continue IV administration for 48 hours after fever disappears then, change to amoxicillin + metronidazole PO to complete 7 days of treatment.

• For the neonate: see Chapter 10, Section 10.1.1 and Section 10.3.3.

– If there are uterine contractions:
• Before 34 weeks LMP: tocolytic agent, except if there are signs of intra-uterine 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 the event of infection, induce labour immediately (Chapter 7, Section 7.3).
• If there is no infection:
- At term: if labour does not start spontaneously, induce labour 12 to 24 hours after rupture of membranes;
- Before term: monitor and, if there are no complications, perform induction at 37 weeks LMP.12
For preterm rupture (< 37 weeks LMP), transfer the mother, if possible, to a facility where the preterm neonate 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 the event of severe maternal infection, start antibiotherapy prior to dexamethasone.