Premature rupture of membranes (PROM) is the breaking of the amniotic sac before labor begins. The sac contains amniotic fluid and the developing baby. With PROM, the amniotic fluid inside the sac leaks or gushes out of the vagina. This is also known as your water breaking.

Fetus with Amniotic Sac
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PROM occurs during the third trimester after 37 weeks of gestation. A related condition called preterm premature rupture of membranes (PPROM) occurs before 37 weeks of gestation.

Call your doctor right away if you suspect that your water has broken.

The causes of PROM are not clearly understood. Some of the possible causes are:

  • Early dilation of the cervix . This may be due to the weight of baby and placenta, or changes in the cervix itself.
  • Infections of the vagina, uterus, or membranes surrounding the fetus.