Bacterial growth in placental swab cultures done among women who received ampicillin prophylaxis for term prelabor rupture of membranes: matched cohort study

  • Melissa Corinales-Lomod Southern Philippines Medical Center
  • Sigrid Aguirre-Barinaga Southern Philippines Medical Center

Abstract

Background. Term prelabor rupture of membranes (PROM) increases the risk of maternal and neonatal infections.
Objective. To compare rates of positive bacterial growth in placental swab cultures done among women who received ampicillin prophylaxis at different timings after term PROM.
Design. Matched cohort study.
Setting. Department of Obstetrics and Gynecology at Southern Philippines Medical Center in Davao City, Philippines.
Participants. 120 pregnant women aged ≥18 years old, at ≥37 weeks age of gestation, with PROM: 40 women received ampicillin within 6 hours (6H group), 40 within >6 to 12 hours (12H group), and 40 within >12 to 18 hours (18H group) of onset of PROM.
Main outcome measures. Rates of positive bacterial growth in postpartum placental swab cultures; most common bacterial isolates; and signs of intraamniotic infection (IAI).
Main results. Women in the 6H group, 12H group, and 18H group did not significantly differ in terms of clinical characteristics at baseline. None of the women developed clinical IAI. Positive bacterial growth were observed in 27/40 (67.5%) of cultures in the 6H group, 31/40 (77.5%) of cultures in the 12H group, and 31/40 (77.5%) of cultures in the 18H group. Across all groups, the five most common isolates were Escherichia coli, Staphylococcus hominis, Staphylococcus haemolyticus, Staphylococcus epidermidis, and Enterobacter cloacae.
Conclusion. Rates of positive bacterial growth in placental swab cultures did not significantly differ among groups of women who received ampicillin at different timings within 18 hours from onset of term PROM.

Published
Dec 31, 2017
Section
Research