Outcome of pregnancies complicated by ruptured membranes after genetic amniocentesis

Abstract

Objective: We sought to compare perinatal outcomes of pregnancies complicated by preterm premature rupture of membranes after genetic amniocentesis with pregnancies complicated by spontaneous preterm premature rupture of membranes at a similar gestational age.

Study design: A retrospective study was performed in which a computerized database was reviewed to identify all patients presenting to our institution with preterm premature rupture of membranes within 48 hours of a genetic amniocentesis from July 1988 to August 1999. Control subjects were matched for gestational age at preterm premature rupture of membranes. Patients were all managed expectantly. Outcomes were compiled from review of medical records. Descriptive statistics, the Student t test, and the chi(2) test were used, with P <.05 considered significant.

Results: During the study period, genetic amniocentesis was performed 1101 times. Eleven (1%) women presented within 48 hours with preterm premature rupture of membranes. The mean gestational age at the time of rupture was not different between the cases in which preterm premature rupture of membranes occurred after genetic amniocentesis compared with the control subjects in whom preterm premature rupture of membranes occurred spontaneously (16.5 weeks vs 17.6 weeks, respectively). Women with preterm premature rupture of membranes after amniocentesis experienced significantly longer latency periods (124 vs 28 days; P =.0001) and delivered at more advanced gestational ages (34.2 vs 21.6 weeks; P =.0002) than those with spontaneous preterm premature rupture of membranes. The perinatal survival rate was 91% in pregnancies complicated by preterm premature rupture of membranes after genetic amniocentesis compared with a rate of 9% in control subjects (P =.005).

Conclusions: Pregnancies complicated by preterm premature rupture of membranes after genetic amniocentesis result in significantly better perinatal outcomes compared with pregnancies complicated by spontaneous preterm premature rupture of membranes at a similar gestational age. Expectant management should be considered in such cases.