Premature rupture of the membranes (PROM) refers to rupture of the fetal membranes prior to the onset of regular uterine contractions. It may occur at term (≥37 weeks of gestation) or preterm (<37 weeks of gestation); the latter is designated preterm PROM (PPROM). Midtrimester PROM typically refers to PPROM at 16 to 26 weeks of gestation; this is an arbitrary definition, which varies slightly among investigators. The frequencies of term, preterm, and midtrimester PROM are approximately 8, 3, and less than 1 percent of pregnancies, respectively.
Management of PROM depends upon several factors, most importantly the gestational age at occurrence and the maternal-fetal clinical condition. The management of PROM at term will be reviewed here. Issues regarding midtrimester PROM and management of PPROM are discussed separately. (See "Midtrimester preterm premature rupture of membranes" and "Preterm premature (prelabor) rupture of membranes".)
Women with term premature rupture of the membranes (PROM) should be evaluated by a clinician. Whether the patient should be evaluated immediately or can remain at home for a few hours to see if labor begins has not been studied. In the absence of high quality data supporting the safety of delaying evaluation, we feel the most prudent approach is prompt assessment to confirm membrane rupture, exclude the presence of infection or a nonreassuring fetal heart rate pattern, determine fetal position, evaluate maternal and fetal well-being, and discuss options for further management.
●The diagnosis of PROM is based upon a characteristic history (ie, leaking fluid per vagina) and speculum examination (ie, visualization of fluid flowing from the cervical os), supplemented by diagnostic testing of fluid in the posterior fornix, if the diagnosis is uncertain. The clinical manifestations and diagnosis of PROM are the same across gestation and are discussed in detail separately. Digital cervicovaginal examination should be avoided, as it has been associated with an increased risk of intrauterine infection. (See "Preterm premature (prelabor) rupture of membranes", section on 'Diagnosis'.)
●Gestational age is determined according to the usual parameters (last menstrual period and/or ultrasound biometry). (See "Prenatal assessment of gestational age and estimated date of delivery".)