Premature Rupture of the Membranes

Introduction

Premature rupture of the membranes is the rupture of the membranes before the onset of labour.
The two types are preterm (before 37 completed weeks) and term (after 37 weeks, but 2 1 hour before onset of labour).

Causes of premature rupture of the membranes

The following are the causes of premature rupture of the membranes

  1. Cervical incompetence
  2. Genital tract infection
  3. Trauma

Symptoms of premature rupture of the membranes

  • Gush or leakage of copious fluid from the vagina

Signs of premature rupture of the membranes

  1. Speculum examination reveals clear fluid from the cervical os or pool of fluid in the posterior vaginal fornix Smaller uterine size for the gestational age
  2. If complicated by infection (chorioamnionitis)
    • Fever
    • Purulent vaginal discharge
  3. Foetal tachycardia or bradycardia
  4. Maternal tachycardia
  5. Uterine tenderness

Investigations

  • FBC
  • Sterile speculum examination including swab for culture
  • Ultrasound scan (if available) for the gestational age, foetal lie and presentation, amniotic fluid volume (normal or reduced), and the placental site.
  • Estimate the foetal weight.
  • Urinalysis and culture

Treatment for premature rupture of the membranes

Treatment objectives

  1. To prevent and/or treat infection
  2. To prevent labour if preterm and baby is very immature
  3. To improve foetal survival through improved foetal lung maturity

Non pharmacological treatment

  • Bed rest

Pharmacological treatment

A. Infection Prevention

1st Line Treatment
Evidence Rating: [B]
Amoxicillin (Amoxycillin), oral,

  • 500 mg 8 hourly for 7 days

And

Metronidazole, oral,

  • 400 mg 8 hourly for 7 days

2nd Line Treatment

Evidence Rating: [C]
Amoxicillin + Clavulanic Acid, oral,

  • 625 mg – 1 g 12 hourly for 7 days

B. Infection Prevention-patients with penicillin allergy

Erythromycin, oral,

  • 500 mg 6 hourly for 7 days

And

Metronidazole, oral,

  • 400 mg 8 hourly for 7 days

Foetal lung maturation – for babies 28-34 weeks
Evidence Rating: [A]
Betamethasone, oral,

  • 0.6-7 mg every 24 hours (2 doses) Or Dexamethasone, oral, 6 mg 12 hourly for (4 doses)

Note

Treatment is most effective if delivery occurs at least 24 hours after the first dose of the medicine has been given and less than 7 days after the last dose of the medicine.
They also benefit the premature newborn by lowering the risk of intraventricular hemorrhage and death.

Referral Criteria

If at sub-district level refer patients to hospital or specialist for further management if signs of maternal infection, pregnancy is less than 37 weeks and or premature labour occurs.