Vaginal Uncomplicated Delivery Rate as a Quality Indicator Compared to Cesarean Delivery Rate: A Quantitative Analysis of a Population Database

Background: Cesarean Delivery rate is a commonly used performance indicator to assess the quality of maternity care, and yet efforts to objectively define the optimal rate have foundered. The Vaginal Uncomplicated Delivery rate was developed as an alternative approach. The Vaginal Uncomplicated Delivery includes all vaginal deliveries, without an adverse labour outcome, whether or not forceps or vacuum were used. By assessing both mode of delivery as well as the absence of maternal and neonatal adverse delivery outcomes, it combines process and outcomes. The objective of this study was to assess the Vaginal Uncomplicated Delivery rate as performance indicator, compared to the Cesarean Delivery rate. Methods : This is a retrospective cohort analysis of a higher risk obstetrical population drawn from the British Columbia Perinatal Data Registry, including all term deliveries by an obstetrician in 2015 in British Columbia, Canada. We excluded proscriptions for active labour, specifically transverse lie, active herpes, placenta previa, and vasa previa. Most obstetricians in this jurisdiction practice consultative obstetrics, focused on supporting primary maternity care. We investigated the association of Adverse Delivery with Cesarean Delivery and Vaginal Uncomplicated Delivery rates. Results: We report 16,620 deliveries by 210 obstetricians, with a vaginal delivery rate of 39.6%, of which 36.6% were operative vaginal delivery. The overall Adverse Delivery rate was 9.9%, and the overall Vaginal Uncomplicated Delivery rate was 34%. While the Cesarean Delivery and Vaginal Uncomplicated Delivery by definition were correlated with mode of delivery, only the Vaginal Uncomplicated Delivery rate was correlated to the Adverse Delivery rate. Conclusions: Quality assurance in obstetrics must balance the needs of two patients based on limited data. Our data suggest that the prevailing performance indicator, Cesarean Delivery rate, fails in this respect because, it does not correlate with birth outcomes for the pregnant patient or infant. The Vaginal Uncomplicated Delivery rate, provides an alternative that correlates with both mode of delivery as a traditional indicator and labour outcomes. Shifting the quality lens to focus on Vaginal Uncomplicated Delivery rate will provide a better metric that measures optimal outcomes for pregnant people, and their babies.