Risk factors for failed induction in nulliparous women

Area of Science:

• Obstetrics and Gynecology
• Maternal-Fetal Medicine
• Reproductive Health

Background:

• Induction of labor (IOL) is a common obstetric procedure.
• Failed IOL can lead to cesarean birth, increasing maternal and neonatal risks.
• Identifying risk factors for failed IOL in nulliparous women is crucial for optimizing obstetric management.

Purpose of the Study:

• To determine independent risk factors associated with failed induction of labor in nulliparous women.
• To differentiate between antenatal and intrapartum risk factors for failed IOL.

Main Methods:

• Retrospective cohort study involving nulliparous women undergoing IOL.
• Comparison of clinical characteristics between women with failed IOL (cesarean birth) and those with successful vaginal birth.
• Statistical analysis to identify independent risk factors using odds ratios (OR).

Main Results:

• 42% of 400 nulliparous women experienced failed IOL.
• Antenatal risk factors included advanced maternal age (OR=1.052/year), shorter maternal height (OR=1.112/cm), and lower cervical dilation (OR=1.411).
• A longer active labor phase (OR=1.004/minute) was the sole intrapartum risk factor for cesarean birth.

Conclusions:

• Maternal age, height, and cervical dilation are significant antenatal predictors of failed IOL.
• The duration of the active labor phase is the primary intrapartum predictor of failed IOL.
• Increased maternal BMI poses a risk, particularly for morbidly obese women, contributing to failed IOL.