Objective: To identify factors associated with cesarean delivery in nulliparous women with type 1 diabetes mellitus.
Methods: We performed a nested case-control study within a cohort of nulliparous women with type 1 diabetes mellitus. Independent factors and odds ratios were identified by logistic regression.
Results: Among 209 women, a cesarean delivery was performed without labor in 94 women (45%). Gestational weight gain higher than 15 kg (39% compared with 23%; odds ratio [OR], 2.2; 95% confidence interval [CI], 1.1-4.5) and suspected macrosomia (79% compared with 21%; OR, 13.1; 95% CI, 5.3-32.2) were independently associated with cesarean delivery without labor. Among 115 women who underwent a trial of labor, 54 (47%) had a cesarean delivery. Prepregnancy body mass index more than 25 kg/m2 (84% compared with 39%; OR, 7.5; 95% CI, 1.9-29.4) and Bishop score 3 or lower (66% compared with 25%; OR, 5.9; 95% CI, 2.2-16.1) were independently associated with cesarean delivery in labor. Preconception care, presence of a nephropathy, hemoglobin A1C levels during pregnancy, preeclampsia, and preterm delivery were not associated with cesarean delivery. The rates of wound infection and endometritis were 0.7% and 3%, respectively.
Conclusion: The rate of cesarean delivery in nulliparous women with type 1 diabetes mellitus is very high. Prepregnancy body weight, gestational weight gain, and accuracy of the prediction of fetal macrosomia are potentially modifiable risk factors for cesarean delivery.