The successful eradication of bacterial colonization of the amniotic fluid with parenteral maternal antibiotic therapy in a preterm gestation with premature rupture of membranes is reported. Amniotic fluid, obtained by amniocentesis, of a pregnancy complicated by premature rupture of membranes at 29 weeks was found to have three different bacterial species (Bacteroides bivius, Veillonella parvula, and Peptococcus). Because of prematurity and clinical quiescence, parenteral antibiotics were administered to the mother. Repeat amniocentesis was performed during treatment and 48 hours after the cessation of antibiotics failed to demonstrate bacterial growth in the amniotic fluid. Fetal lung maturity was attained, and an induction of labor was performed when antepartum heart rate testing was equivocal. This was accomplished without maternal or fetal/neonatal mishap.