(526) Association between antibiotic regimen and adverse outcomes in pregnancies complicated by chorioamnionitis

Passive prospective, single center, cohort study of pregnancies complicated by chorioamnionitis treated with either intravenous ampicillin, gentamicin, ± clindamycin (AGC, 2010-2017) or piperacillin/tazobactam with clindamycin (PTC, 2017-2021). Acute chorioamnionitis was defined based on accepted clinical and histopathological criteria. We assessed the univariate associations between pregnancy characteristics and antibiotic regimen administered in addition to our composite adverse outcome: maternal sepsis, atonic postpartum hemorrhage, and/or neonatal sepsis with antibiotic administration prior to delivery, readmission for endometritis, wound infection, and/or maternal temperature of 99.5 for >24 hours after administration of first antibiotic dose. Factors with P < 0.2 on one or both univariate analyses were considered for incorporation into a multivariable model predictive of the primary outcome.


Results:

Of 403 pregnancies, 211 were treated with AGC vs 192 with PTC regimens. Most characteristics were similar between antibiotic regimen groups, however women receiving AGC were younger and fewer had a public payor source. The 88 (22%) pregnancies with the primary outcome had a longer median duration of rupture of membranes prior to delivery (20.6 vs 14.3 hours, P < 0.01), more underwent cesarean delivery (CD) (36% vs 11%, P < 0.0001), and more received the AGC regimen (27 % vs 16%, P 0.01). Factors associated with the primary outcome on multivariable analysis include BMI >30, substance use, delivery < 37 weeks, CD, and treatment with AGC regimen (aOR 2.15, 95% CI 1.08-3.46). The 5-covariate model had an optimism-corrected bootstrapped (1000 replicates) AUROC of 0.76 (95% CI 0.69-0.80).

Conclusion:

Treatment of intrapartum acute chorioamnionitis with the PTC regimen has the potential to lead to improved maternal and neonatal outcomes.