This study evaluates the impact of gestational weight gain (GWG) on the risk for operative vaginal delivery across the spectrum of maternal pre-pregnancy body mass index (PPBMI).METHODS:
Vital statistics data collected by the National Center for Health Statistics (NCHS) were utilized. Using the 2015 data, GWG was calculated and the birth cohort consisting of singleton gestations delivering vaginally was classified into inadequate, adequate and excess GWG categories as per the 2009 Institute of Medicine (IOM) guidelines. Each PPBMI category was further stratified based on the adequacy of GWG. Multivariate logistic regression analyses were used to predict the risk for operative vaginal delivery in each PPBMI and GWG group while adjusting for age, race, ethnicity, education, marital status, insurance and smoking status.RESULTS:
The rate of operative vaginal delivery in this study cohort was 4.63% (116,610/2,517,605 singleton vaginal deliveries). Excess GWG significantly increased the risk for an operative vaginal delivery (OR 1.074 [95% CI 1.060 - 1.089]) irrespective of the PPBMI, in the adjusted regression analyses. In the PPBMI specific analyses - the risk for operative vaginal delivery was significantly increased in women with excess GWG in women classified as underweight OR 1.118 (95% CI 1.047-1.194), normal weight OR 1.112 (95% CI 1.092-1.134), overweight OR 1.145 (95% CI 1.112-1.179), and obese OR 1.148 (95% CI 1.108-1.189) as compared to those in the same weight categories with adequate GWG.CONCLUSION:
Our findings demonstrate that women with excess GWG, regardless of their pre-pregnancy maternal weight category, are at increased risk of undergoing operative vaginal delivery.