Induction of labor and cesarean birth in lower‐risk nulliparous women at term: A retrospective cohort study

• Published in: Birth (Berkeley, Calif.) Calif.), 2024-09, Vol.51 (3), p.521-529
• Main Authors: Butler, Sarah E., Wallace, Euan M., Bisits, Andrew, Selvaratnam, Roshan J., Davey, Mary‐Ann
• Format: Article
• Language: English
• Subjects: Births; cesarean birth; Childbirth & labor; Clinical trials; Cohort analysis; Gestational age; Induced labor; Induction; induction of labor; low‐risk pregnancy; Mortality; Perinatal mortality; Pregnancy; Statistical significance; Stillbirth; Women
• ISSN: 0730-7659; 1523-536X; 1523-536X
• DOI: 10.1111/birt.12806

Objective To evaluate whether induction of labor (IOL) is associated with cesarean birth (CB) and perinatal mortality in uncomplicated first births at term compared with expectant management outside the confines of a randomized controlled trial. Methods Population‐based retrospective cohort study of all births in Victoria, Australia, from 2010 to 2018 (n = 640,191). Preliminary analysis compared IOL at 37 weeks with expectant management at that gestational age and beyond for uncomplicated pregnancies. Similar comparisons were made for IOL at 38, 39, 40, and 41 weeks of gestation and expectant management. The primary analysis repeated these comparisons, limiting the population to nulliparous women with uncomplicated pregnancies and excluding those with a medical indication for IOL. We compared perinatal mortality between groups using Chi‐square tests and multivariable logistic regression for all other comparisons. Adjusted odds ratios and 99% confidence intervals were reported. p