Rupture of membranes

Question 1

Types of rupture of membranes?

Answer 1

• Spontaneous rupture of membranes (normal, spontaneous rupture of membranes at term
• Prelabor rupture of membranes (PROM) (Rupture of membranes prior to the onset of labour and over 37 completed weeks of gestation)
• Premature prelabour rupture of membranes (rupture before 37 weeks)

Question 2

Causes of prelabor rupture of membranes

Answer 2

Malpresentation
Multiple pregnancy
Polyhydramnios
Infection of the lower genital tract

Question 3

What compound is produced when the amniotic sac ruptures?

Answer 3

Prostaglandins –> stimulating contractions

Prostaglandin 2F-alpha

Question 4

Complications of prelabour rupture of membranes?

Answer 4

Endometritis
Chorioamnionitis

Preterm delivery often follows preterm prelabour rupture of membranes

Question 5

Investigations

Answer 5

Speculum exam –> pool of fluid in posterior fornix is diagnostic
If -ve results, perform amnisure test, if still -ve unlikely to be PROM

Calculate Amniotic Fluid Index
To look for infection –> HVS, FBC, CRP
CTG to monitor fetal well-being

Question 6

Treatment if less than 37 weeks?

Answer 6

Prophylactic Abx: Erythromycin for 10 days 
Consider steroids (offer if between 26 and 33+ 6 days)
Induction of labour if not gone into labour within 24hours

Question 7

Treatment if more than 37 weeks?

Answer 7

Conservative Mx (Do not offer prophylactic Abx!)
Induction of labour if not gone into labour within 24 hours

Question 8

Indications for immediate induction in rupture of membranes?

Answer 8

Clinical signs of infection
Concerns regarding fetal movements
GBS carrier
HIV carrier