Labor Induction in Obese Pregnancies at Term: Risk Factors and Pregnancy Outcomes

The objectives of this study are to identify risk factors associated with failed labor induction in obese pregnancies at term and evaluate related maternal and neonatal outcomes.

This cross-sectional study included obese pregnant women (BMI ≥ 30 kg/m²) who underwent labor induction at 37-41 weeks' gestation in two academic hospitals in Surabaya, Indonesia, during 2023. Participants were classified into successful and failed induction groups. Maternal characteristics, induction-related factors, and pregnancy outcomes were compared. Multivariable logistic regression was used to identify independent risk factors for induction failure.

A total of 159 women were included, comprising 53 failed and 106 successful inductions. Failed induction was significantly associated with primiparity (adjusted odds ratio [aOR], 3.10; 95% CI, 1.46-6.58), Bishop score < 3 (aOR, 2.02; 95% CI, 1.14-3.55), and higher maternal weight gain during pregnancy (aOR per kg increase, 0.89; 95% CI, 0.84-0.95). Maternal weight gain demonstrated a moderate effect size (standardized mean difference, 0.62). Compared with successful induction, failed induction was associated with higher rates of severe preeclampsia (18.9% vs. 1.9%), cesarean delivery (100% vs. 5.7%), longer hospitalization, and lower 1-min Apgar scores. No significant differences were observed in 5-min Apgar scores, fetal growth restriction, congenital anomalies, or NICU admission.

In obese pregnancies at term, primiparity, unfavorable cervical status, and excessive gestational weight gain are independently associated with failed labor induction. These findings highlight the importance of optimized patient selection, cervical assessment, and anticipatory counseling to improve maternal and neonatal outcomes.