<P> Most women will experience a painless leakage of fluid out of the vagina . They may notice either a distinct "gush" or a steady flow of small amounts of watery fluid in the absence of steady labor contractions . Loss of fluid may be associated with the fetus becoming easier to feel through the belly (due to the loss of the surrounding fluid), decreased uterine size, or meconium (fetal stool) seen in the fluid . </P> <P> 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 . </P> <Ul> <Li> Infections: urinary tract infection, sexually transmitted diseases, lower genital infections (e.g. bacterial vaginosis), infections within the amniotic sac membranes </Li> <Li> Cigarette smoking during pregnancy </Li> <Li> Illicit drug use during pregnancy </Li> <Li> Having had PROM or preterm delivery in previous pregnancies </Li> <Li> Polyhydramnios: too much amniotic fluid </Li> <Li> Multiple gestation: being pregnant with two or more fetuses at one time </Li> <Li> Having had episodes of bleeding anytime during the pregnancy </Li> <Li> Invasive procedures (ex: amniocentesis) </Li> <Li> Nutritional deficits </Li> <Li> Cervical insufficiency: having a short or prematurely dilated cervix during pregnancy </Li> <Li> Low socioeconomic status </Li> <Li> Being underweight </Li> </Ul> <Li> Infections: urinary tract infection, sexually transmitted diseases, lower genital infections (e.g. bacterial vaginosis), infections within the amniotic sac membranes </Li>

What causes a rupture in the amniotic sac
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