Gestational weight gain and mode of delivery by the class of obesity: A meta-analysis

The association between gestational weight gain (GWG) and mode of delivery in females with different obesity classes is not clear. We conducted a meta-analysis to evaluate the association between GWG, categorized according to the 2009 Institute of Medicine (IOM) guidelines, and the risk of cesarean section (CS) or operative vaginal delivery (OVD) in females with different obesity classes. Eight studies were identified. The pooled odds ratios (ORs) (95% confidence interval [CI]) of CS for females with GWG above the recommendations were 1.27 (1.20-1.33) for obesity class I, 1.22 (1.20-1.23) for class II, and 1.17 (1.15-1.19) for class III. Also, the pooled ORs (95% CI) of OVD were 1.21 (1.005-1.46) for obesity class I, 1.12 (1.04-1.21) for class II, and 1.10 (1.001-1.22) for obesity class III. GWG below the recommendations was associated with lower risk of CS for females with obesity class I (OR 0.87, 95% CI 0.82-0.92), class II (OR 0.84, 95% CI 0.77-0.90), and class III (OR 0.86, 95% CI 0.79-0.93). Pregnant participants gaining weight above the 2009 IOM guidelines were at higher risk for CS and OVD regardless of obesity classes. Gaining weight below the guidelines was associated with a lower risk of CS among females in any obesity class.