Rates of Vaginal Delivery With Increasing Cervical Dilation After Cervical Ripening and Advanced Maternal Age [ID: 1372406

Abstract

INTRODUCTION: Pregnant patients of advanced maternal age (AMA) are at an increased risk for cesarean delivery. Our primary objective was to determine the association between cervical dilation after cervical ripening and vaginal delivery rates for AMA versus non-AMA patients. METHODS: This was an IRB-approved, retrospective cohort study conducted at a single tertiary care center, which included nulliparous, term deliveries that required cervical ripening from January 2020 to January 2022. We excluded patients with multifetal gestation, pregestational diabetes, lethal fetal anomalies, prior cesarean delivery, and prisoner status. RESULTS: Altogether, 964 patients met inclusion/exclusion criteria, of whom 17.7% were AMA. Increasing cervical dilation at the end of cervical ripening was associated with higher rates of vaginal delivery, with a mean of 3.7 cm for patients who underwent vaginal delivery and 3.2 cm for those who delivered via cesarean (P<.001). A logistic regression examined the interaction between AMA status with cervical dilation after ripening and vaginal delivery rates, which was not significant (P=.38). After adjusting for AMA status, the odds of having a vaginal delivery increased by 22% for every 1-unit increase in end cervical dilation after ripening (CI 1.12–1.33, P<.001). Compared to non-AMA, after adjusting for end dilation after ripening, AMA patients were 35% less likely to have a vaginal delivery (CI 0.46–0.91, P=.013). CONCLUSION: Advancing cervical dilation after ripening was associated with a higher rate of vaginal delivery overall. However, AMA patients had significantly fewer vaginal deliveries even when controlling for this end cervical dilation.