Single additional dose postpartum therapy for women with chorioamnionitis

To determine whether a short course of antibiotics provides adequate treatment for chorioamnionitis.

Women received intravenous ampicillin, 2 g every 6 hours, and gentamicin, 1.5 mg/kg every 8 hours, when clinical chorioamnionitis was diagnosed. After delivery, subjects were randomized to continue this regimen until afebrile and asymptomatic for 24 hours (control group) or to receive only the next scheduled dose of each drug (study group). If delivered via cesarean, patients received clindamycin, 900 mg intravenously, at umbilical cord clamping. The control group continued receiving clindamycin every 8 hours until antibiotics were discontinued. The primary outcome was treatment failure, defined as a single temperature after the first postpartum dose of antibiotics of 39.0C or more, or two temperatures 38.4C or more at least 4 hours apart. To detect a 150% increase in rate of treatment failures from 8% in the control group to 20% in the study group, 292 subjects were needed (alpha = .05; 1 - beta = .80).

From December 26, 1999, to March 18, 2003, a total of 292 women were enrolled in the study. In the intent-to-treat analysis, treatment failure rate did not differ between the control (n = 141) and study (n = 151) groups (3.5% versus 4.6%; P = .639).

If treated promptly intrapartum, one additional dose of a broad-spectrum combination of antibiotics is sufficient postpartum therapy for immune-competent women with chorioamnionitis.