Maternal "isolated" obesity and obstetric complications

Objective: To investigate pregnancy outcomes, particularly cesarean delivery (CD), among women with "isolated" obesity (i.e. without additional comorbidities). Study design: We conducted a retrospective population-based study between the years 1988-2010. The pregnancy outcomes of obese (prepregnancy BMI >= 30 kg/m(2)) and nonobese patients were compared. Patients with chronic hypertension, pregestational diabetes mellitus, other preexisting chronic morbidities, multiple gestations, age above 40 years, grand multiparity (above 5 deliveries), lack of prenatal care, and following fertility treatments were excluded from the analysis. Stratified analyses, using multiple logistic regression models, were performed to control for confounders. Results: During the study period, a total of 173,628 deliveries met the inclusion criteria; 1605 (0.9%) occurred in patients with "isolated" obesity. Higher rates of CD were found among patients with "isolated" obesity (30.7% vs. 12.3%; odds ration [OR] = 3.2; p < 0.001). When controlling for possible confounders, using a multivariable model with CD as the outcome variable, the association between "isolated" obesity and CD remained significant (adjusted OR = 2.6; p < 0.001). No significant differences were found in the risks of perinatal complications including perinatal mortality, shoulder dystocia, congenital malformations, and low 5-min Apgar score. Conclusion: "Isolated" obesity, although not a risk factor for adverse perinatal outcomes, is an independent risk factor for CD.