764 Operative vaginal delivery as an independent risk factor for maternal postpartum infection

Abstract

Recent studies suggest prophylactic antibiotics are effective in reducing maternal postpartum (PP) infection following operative vaginal delivery (OVD). There is limited data in the US, where episiotomy and laceration repair practices may differ, affecting the risk of PP infection after OVD. We sought to evaluate whether OVD is an independent risk factor for maternal PP infection. Retrospective cohort study of all singleton vaginal deliveries >34 weeks’ gestation at a single perinatal center (2013-2018). Women were categorized by mode of delivery: spontaneous vaginal delivery (SVD) or OVD (forceps/vacuum assisted). The primary outcome was a composite of confirmed or suspected maternal infection up to 6 weeks after delivery defined as: (1) endometritis (CDC definition), (2) perineal wound morbidity (infection or breakdown) or (3) culture proven urinary tract infection. Outcomes were compared between groups; multivariable generalized estimating equations were used to estimate the adjusted odds ratios (95% CI) with SVD as the reference group. Of 14,646 deliveries meeting inclusion criteria, 732 (5%) were OVDs. The overall composite rate was 1.4%. Women undergoing an OVD were more likely to be nulliparous, undergo labor induction, develop chorioamnionitis, have an episiotomy, and sustain a 3rd/4th degree laceration (Table 1). After controlling for these known confounders, there was no difference in composite infection following OVD compared to SVD (aOR 1.28 [0.73-2.23]) or any of its individual components (Table 2). There were no differences in receipt of PP antibiotics or PP fever. We considered the individual contribution of forceps (p=0.20) vs vacuum (p=0.95) on the adjusted odds of the composite outcome, which indicated no differences by instrument. Accounting for risk factors associated with PP infection and the need for OVD, OVD itself does not appear to be an independent risk factor for maternal PP infection in our population. Routine use of prophylactic antibiotics with OVD may not be warranted based on contemporary 2nd stage labor management patterns in the US.View Large Image Figure ViewerDownload Hi-res image Download (PPT)