Premature rupture of membranes before 34 weeks managed expectantly: maternal and perinatal outcomes in singletons

To ascertain the risk factors for imminent delivery and infection in pregnant women with premature rupture of membranes (PPROM) before 34 weeks of gestation, evaluate maternal and fetal outcomes and identify obstetric factors for determining which patients meet the criteria for home follow-up.

Medical charts of all women with PPROM admitted to the Vall d'Hebron Hospital (HVH) between January 2006 and December 2010 were retrospectively reviewed.

During the study period, 216 women were admitted with a diagnosis of PPROM <34 weeks of gestation with a singleton, live, structurally-normal fetus. Mean gestational age at delivery was 31 weeks. Sixty-two patients (28.7%) delivered before 28 weeks and 76 of the infants (35.2%) had birth weight <1,500 g. Overall, 202 infants (93.5%) survived to be discharged home. On stratifying by gestational age at PPROM diagnosis, prognosis was better when PPROM occurred near to term. Gestational age at delivery was increased in pregnant women with no oligohydramnios, no shortened cervix and with negative endocervical and vaginal cultures at PPROM diagnosis (33 weeks of gestation) vs. pregnant women with positive cultures at admission (27 weeks), oligohydramnios at admission (28 weeks) and shortened cervix (26 weeks). This difference was statistically significant (p = 0.005).

Protective factors for PPROM could be normal AFI, cervical length >25 mm and negative cultures at PPROM diagnosis. These factors could permit home follow-up of this group of patients.