Expanded-spectrum antibiotics with preterm premature rupture of membranes

Objective: To compare maternal infection rates, neonatal sepsis rates, and bacterial resistance patterns in cases of neonatal sepsis for three antibiotic protocols for women with preterm premature rupture of membranes (PROM). Methods: From January 1, 1988 to February 28, 1998, women with preterm FROM not requiring immediate delivery were treated according to one of three antibiotic protocols. During three distinct periods, patients received no antibiotics, intravenous ampicillin for 48 hours followed by oral amoxicillin, or intravenous ticarcillin-clavulanic acid for 48 hours followed by oral amoxicillin-clavulanic acid, Rates of chorioamnionitis, endometritis, and neonatal sepsis were compared, as were antimicrobial resistance patterns. Statistical analysis was done using chi(2) analysis, Fisher exact test, and the log-likelihood ratio test. The Bonferroni correction was used for multiple comparisons. Results: During the three periods, preterm FROM was diagnosed in 1695 women. The incidence of endometritis was lower during the third (5.3%) compared with the first (15.1%, P <.001) and second (11.6%, P <.001) protocols. Chorioamnionitis rates were 13.6%, 12.7%, and 15.6% (P =.34) for the first, second, and third periods, respectively, and neonatal sepsis rates were 2.2%, 0.6%, and 1.1% (P =.08), respectively. Neonatal sepsis with gram-negative (P =.02) and ampicillin-resistant (P =.04) organisms was more likely when mothers received antepartum ampicillin or ticarcillin-clavulanic acid. Conclusion: Antibiotic therapy for patients with preterm FROM was associated with a decrease in the rate of endometritis and a trend toward less neonatal sepsis but an increase in the proportion of gram-negative and ampicillin-resistant organisms causing neonatal sepsis. (Obstet Gynecol 2000;96:60-4. (C) 2000 by The American College of Obstetricians and Gynecologists.).