Nulliparous with Class III Obesity at Term: Labor Induction or Cesarean Delivery without Labor

This study aimed to compare maternal and neonatal outcomes between labor induction versus cesarean delivery (CD) without labor among nulliparous individuals with class III obesity (body mass index [BMI] ≥40 kg/m²).

A retrospective cohort study of all nulliparous singleton deliveries at ≥37 weeks with a BMI of ≥40 kg/m² at delivery between March 2020 and February 2022. We excluded individuals with spontaneous labor, fetal malformations, and stillbirths. The primary outcome was a composite of maternal mortality and morbidity, including infectious and hemorrhagic morbidity. The secondary outcome was a neonatal composite. A subgroup analysis evaluated patients with a BMI of ≥50 kg/m². Another subgroup analysis compared outcomes between CD without labor and an indicated CD following induction. A multivariable logistic regression was applied. For adjustment, we used possible confounders identified in a univariate analysis.

Among 8,623 consecutive deliveries during the study period, 308 (4%) met the inclusion criteria. Among them, 250 (81%) underwent labor induction, and 58 (19%) had a CD without labor. The most common indications for CD without labor were fetal malpresentation (26; 45%), suspected macrosomia (8; 14%), and previous myomectomy (5; 9%). Indicated CD occurred in 140 (56%) of the induced individuals, with the two leading indications being labor arrest (87; 62%) and non-reassuring fetal heart rate tracing (51; 36%). The rates of composite maternal morbidity (adjusted odds ratio [aOR] = 2.14, 95% confidence interval [CI]: 0.64-7.13) and composite neonatal morbidity (aOR = 3.62, 95% CI: 0.42-31.19) did not differ following a CD without labor compared to labor induction. The subgroup analyses did not demonstrate different outcomes between groups.

Among nulliparous individuals with class III obesity at term who underwent induction, more than 50% had indicated CD; the rate of short-term maternal and neonatal morbidity, however, did not differ between labor induction and CD without labor.

· The rate of unplanned CD among those who underwent labor induction was relatively high (56.0%).. · Outcomes did not differ between those who underwent CD without labor and those who were induced.. · Outcomes also did not differ between those who underwent CD without labor and those with CD in labor..