Optimal antenatal management for women with advanced maternal age (AMA) is not known. Our objective was to determine if induction of labor (IOL) in nulliparous women with AMA (age 35–39) compared to women with very AMA (VAMA, age ≥40) is associated with an increased risk of adverse outcomes, such as rate of cesarean delivery (CD).
A retrospective cohort study of patients ≥35 years who underwent IOL at a single tertiary care center from June 2011 to December 2014. Obstetric and neonatal outcomes were compared after dichotomization into groups 35–39 and ≥40 years.
From a total 428 patients who met inclusion criteria, 273 (64%) comprised the AMA group and 155 (36%) the VAMA group. The AMA cohort had a higher Bishop score on admission compared to the VAMA cohort. IOL for late term was the most common indication in the AMA group (33.7%) and IOL for AMA in the VAMA group (58.1%). The CD rate was higher in the VAMA group (56.1% versus 44.3%, P=.02). This difference was not significant when controlling for Bishop score <5. The most common indications for CD were arrest of dilation (38.3%) in the AMA group and failed IOL (32.2%) in the VAMA group. When stratified by age, there was a significant increase in CD rate by increasing maternal age (P=.002).
Nulliparous women ≥35 year old who undergo IOL have a high likelihood of CD, with increasing rates as maternal age increases. This information can guide clinicians when discussing delivery options with nulliparous patients age ≥35.