Determinants and outcomes of cesarean delivery on maternal request (CDMR): A population-based study in Ontario, Canada

Abstract

<h3>Objectives</h3> To evaluate the trends, determinants and outcomes of CDMR in Ontario. <h3>Methods</h3> This was a population-based retrospective cohort study of singleton pregnancies in Ontario from 2012 to 2017. Multivariate logistic regression models were used to examine the association of sociodemographic, obstetric and neonatal factors with CDMR. Outcomes were assessed via an ‘intent-to-treat' approach. Generalized estimating equation models with log-link function were used to estimate the adjusted risk ratio of the Adverse Outcome Index (AOI) between planned CDMR and vaginal births. Differences of Weighted Adverse Outcome Score (WAOS) and Severity Index (SI) between planned mode of delivery were compared. <h3>Results</h3> Of 668,468 women, 0.7% (4,821) planned CDMR and 85.6% (569,212) planned vaginal deliveries. The prevalence of CDMR was stable at 3.0% of all cesarean deliveries. Older age, higher education, IVF, anxiety, nulliparity, Caucasian race and maternal level IIc hospital deliveries were associated with CDMR. The AOI rate was 5.6% for planned CDMR and 10.3% for planned vaginal birth. Women who planned CDMR had fewer adverse outcomes than women who planned vaginal deliveries (aRR:0.59 [95% CI 0.52–0.67]). The WAOS was lower for planned CDMR than planned vaginal delivery (2.6 v 3.6). The SI was higher with planned CDMR (47.5 v 34.5), in part due to points accumulated from "unanticipated operative procedures." <h3>Conclusions</h3> CDMR rates have not increased in Ontario over the last 5 years. Planned CDMR is associated with decreased risk of short-term adverse outcomes, compared to planned vaginal delivery. Analysis of longer-term breastfeeding, infant and pediatric outcomes following CDMR is warranted.