Premature rupture of membranes | |
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A fetus surrounded by the amniotic sac which is enclosed by fetal membranes. In PROM, these membranes rupture before labor starts. | |
Classification and external resources | |
Specialty | obstetrics |
ICD-10 | O42 |
ICD-9-CM | 658.1 |
DiseasesDB | 10600 |
eMedicine | med/3246 |
MeSH | D005322 |
Premature rupture of membranes (PROM), or pre-labor rupture of membranes, is a condition that can occur in pregnancy. It is defined as rupture of membranes (breakage of the amniotic sac), commonly called breaking of the mother's water(s), more than 1 hour before the onset of labor. The sac (consisting of 2 membranes, the chorion and amnion) contains amniotic fluid, which surrounds and protects the fetus in the uterus (womb). After rupture, the amniotic fluid leaks out of the uterus through the vagina.
Women with PROM usually experience a painless gush of fluid leaking out from the vagina, but sometimes a slow steady leakage occurs instead.
When premature rupture of membranes occurs at or after 38 weeks completed gestational age (at term), there is minimal risk to the fetus and labor typically starts soon after.
If rupture occurs before 37 weeks, called preterm premature rupture of membranes (PPROM), the fetus and mother are at greater risk for complications. PPROM causes one-third of all preterm births, and babies born preterm (before 37 weeks) can suffer from the complications of prematurity, including death. Open membranes provide a path for bacteria to enter the womb and puts both the mother and fetus at risk for life-threatening infection. Low levels of fluid around the fetus also increase the risk of the umbilical cord compression and can interfere with lung and body formation in early pregnancy.
Women who experience premature rupture of membranes should be evaluated promptly in the hospital to determine if a rupture of membranes has indeed occurred, and to be treated appropriately to avoid infection and other complications.
Most women will experience a painless gush of fluid that leaks out of the vagina. Sometimes women notice a steady leakage of small amounts of watery fluid rather than a distinct "gush". Other symptoms include a change in color and consistency of fluid coming out of the vagina, flecks of meconium (fetal stool) in the fluid, or a decrease in the size of the uterus.
The cause of premature rupture of membranes (PROM) is not clearly understood, but the following are risk factors that have been shown to increase the chance of it happening. In many cases, however, no risk factor is identified.