Optimal Plan for Delivery in Women with Obesity: A Large
Population-based Retrospective Cohort Study Using the Better Outcomes
Registry and Network (BORN) Database
Abstract
Objective: To discern the optimal plan for delivery in nulliparous women
with obesity at term gestation. Design: Large population-based
retrospective cohort study Setting: Maternity hospitals in Ontario,
Canada Population: Nulliparous women with obesity (BMI>30)
with live, singleton, uncomplicated term gestations (37+0 to 41+6 weeks)
between April 1st, 2012 and March 31st, 2019 Methods: Women were divided
by plan for delivery (expectant management, induction of labour and
no-labour caesarean section). The outcomes of interest were adverse
delivery outcomes. Analyses were conducted using multivariable
regression models. Analyses were stratified by each week of gestational
age and by obesity class. Main Outcome Measures: The primary outcome was
the Adverse Outcome Index (AOI), a binary composite of 10 maternal and
neonatal adverse events. The Weighted Adverse Outcome Score (WAOS) was
the secondary outcome. It provides a weighted score of each adverse
event included in the AOI. Results: No-labour caesarean section reduced
the risk of adverse delivery outcome by 41% (aRR 0.59, 95%CI [0.50,
0.70]) compared to expectant management at term gestation. There was
no statistically significant difference in adverse birth outcomes when
comparing induction of labour to expectant management (aRR 1.03, 95% CI
[0.96, 1.10]). The greatest benefit to no-labour caesarean section
was observed in the reduction of adverse neonatal events (aRR 0.70, 95%
CI [0.57, 0.87]) particularly at 39 weeks of gestation. Conclusion:
In women with obesity, no-labour caesarean section reduces adverse birth
outcomes. Funding: Canadian Institute for Health Research (CIHR)
(#MFM146444). Keywords: Plan for delivery, Induction of Labour,
Caesarean Section, Obesity