Chorioamnionitis Is an Independent Risk Factor for Third- and Fourth-Degree Perineal Lacerations in the United States [ID: 1377609]

INTRODUCTION: The objective was to determine the effect chorioamnionitis has on the risk of third- and fourth-degree perineal lacerations (3/4 PL). METHODS: This represents a retrospective cohort based on the Centers for Disease Control and Prevention Natality Live Birth database (2016–2020). We compared the rates of 3/4 PL in term, singleton vaginal births across the United States based on diagnosed intrapartum chorioamnionitis. We used Pearson chi-square and multivariate logistic regression to control for confounding variables. Statistical significance was determined as P <.05, and results were displayed as adjusted odds ratios (aORs) with 95% CI. RESULTS: Of the 11,677,671 who met inclusion criteria, 139,174 (1.2%) women experienced 3/4 PL. Intrapartum chorioamnionitis was associated with a staggering 3.96% rate of 3/4 PL compared to a 1.15% rate in women without chorioamnionitis (aOR 1.85, 95% CI 1.80–1.90). CONCLUSION: Based on this current U.S. database we identified chorioamnionitis as a major risk factor for 3/4 PL. The potential explanation may be due to dysfunctional labor, increased perineal edema secondary to protracted labor, or increased friability of tissue. Understanding this association may assist in better counseling and potentially reduce the rates of 3/4 PL in gravidas with chorioamnionitis.