Before a baby is born, the
amniotic sac breaks open, causing amniotic fluid to
gush out or, less commonly, to slowly leak. When this happens before
contractions start, it is called premature rupture of membranes (PROM). PROM
can occur at any time during pregnancy.
When PROM occurs before
37 completed weeks of pregnancy, it usually leads to
preterm labor. You may hear this early PROM referred
to as preterm premature rupture of membranes, or pPROM.
PROM is often unexpected, and the cause is often
difficult to identify. Known causes of PROM include:
- Uterine infection, which is a common trigger of
pPROM.
- Overstretching (distension) of the uterus and amniotic sac.
Multiple fetuses or too much amniotic fluid (polyhydramnios) are common causes
of distension.
- Trauma, as from a motor vehicle accident.
Course of pPROM
Preterm labor usually begins shortly
after pPROM occurs. Sometimes, when a slow leak is present and infection has
not developed, contractions may not start for a few days or longer. In general,
the later in a pregnancy PROM occurs, the sooner the onset of labor.
Sometimes a leak high up in the amniotic sac may reseal itself so that
preterm labor does not start or subsides.
In rare cases, a
pregnancy can be carried to term if pPROM occurs in the second
trimester.
Standard treatment for pPROM
Standard treatment for pPROM includes antenatal corticosteroid
medicines, which are used to speed up fetal lung maturity at or before 34 weeks
of pregnancy.
Other treatment for pPROM
Other treatment for pPROM may include:
- An observation period or
expectant management.
- Antibiotics, given to treat or prevent amniotic fluid
infection.
- Amniocentesis, which is sometimes used
to check for infection in the uterus or check to see if the fetus's lungs are
mature enough for delivery.
- Starting (inducing) labor with medicine if labor does not start
naturally. This is meant to speed up delivery and reduce the risk of infection.
Labor can be induced if there is strong evidence that the fetus's lungs are
mature enough, or if you have an infection.
Controversial treatment for pPROM
After amniotic
membranes have ruptured,
tocolytic medicine is less effective in slowing or
stopping preterm labor contractions. But tocolytic medicine is sometimes used
to delay a preterm birth long enough for antibiotics and antenatal
corticosteroid medicine to work (24 hours) or long enough to transport the
mother to a hospital that has a neonatal intensive care unit (NICU).1