What is premature rupture of membranes?
Premature rupture of membranes (PROM) is defined as rupture of membranes at 37 weeks gestation or beyond and which occurs prior to the onset of labor. Other forms of PROM are:
- Preterm premature rupture of membranes (PPROM) – rupture of membranes (ROM) occurring before 37 weeks of gestation
- Spontaneous PROM (SPROM) – ROM occurring with or after the onset of labor
- Prolonged ROM – any ROM lasting for 24 hours or longer and prior to the onset of labor
What causes it?
ROM is a normal process that is caused by programmed cell death, mechanical forces, and catabolic enzymes, such as collagenase. PROM and PPROM result from the same factors involved in ROM but which are prematurely activated. In addition, early PROM may be caused by infection and/or inflammation of the membranes. Clinical factors associated with PROM include:
- Low body mass index
- Tobacco use
- History of preterm labor
- Amniocentesis
- Urinary tract infection
- Vaginal bleeding during pregnancy
- Cerclage
Incidence and management of ROM
PROM is the leading cause of preterm birth, occurring in 30% to 40% of preterm deliveries, and complicates approximately 3% of all pregnancies. In the USA, approximately one woman in 150,000 will experience PROM per year. If PPROM happens very early on, there are significant risks in both mortality and morbidity for baby and mother.
The fetal membranes act as a barrier to infection and once ROM occurs, delivery is recommended when the risk of infection outweighs the risk of prematurity, usually at a time point after 34 weeks. If ROM occurs at term, an induction is usually performed within 12 – 24 hours if labor doesn’t spontaneously follow. Preterm PROM is managed according to each woman’s situation.
Treatment of PROM and PPROM and their complications
Substantial evidence now exists to support the use of broad-spectrum antibacterials to prolong latency, defined as the time from ROM to delivery. In addition, antibacterials to prevent infection by Group B beta-hemolytic Streptococcus (GBS) administered during preterm birth have been shown to prevent GBS-associated blood infections.
Corticosteroids have been shown to reduce the risk of respiratory distress syndrome, intraventricular hemorrhage, and necrotizing enterocolitis in 50% of women with potential impending PROM.
Can the membranes reseal?
In the majority of patients with PROM following amniocentesis, the membranes will reseal and the normal volume of amniotic fluid is usually replenished. Resealing of the membranes is far less common in spontaneous PROM, occurring in between 2.8% to 13% of cases. Various treatments have been developed that attempt to artificially reseal the fetal membranes, such as patching and sealing the cervical canal; however, as yet, there is still no effective resealing treatment for PROM.
