The relationship between maternal age and uterine dysfunction: a continuous effect throughout reproductive life

Area of Science:

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

Background:

• Uterine function is critical for labor progression.
• The influence of maternal age on labor outcomes, particularly in low-risk populations, requires further elucidation.
• Previous studies suggest increased risks with advanced maternal age, but continuous effects are less understood.

Purpose of the Study:

• To investigate the continuous effect of maternal age on uterine function in a low-risk population experiencing spontaneous term labor.
• To analyze the relationship between maternal age and measures of labor dysfunction and operative delivery rates.

Main Methods:

• Analysis of a comprehensive database of 8496 nulliparous patients in spontaneous term labor with singleton vertex fetuses.
• Stratification of patients by maternal age.
• Statistical analysis using analysis of variance and chi(2) statistics to assess labor dysfunction and delivery outcomes.

Main Results:

• Significant increases in oxytocin use, duration of the second stage of labor, cesarean delivery rates, and operative vaginal delivery rates were observed with advancing maternal age (P <.0001).
• These increases demonstrated a continuous pattern, commencing in the early 20s, rather than a threshold effect after age 35.
• Cesarean delivery for failure to progress also showed a continuous increase with maternal age.

Conclusions:

• Maternal age exerts a continuous influence on uterine function, leading to increased risks of labor dysfunction.
• Even in nulliparous patients with initially uncomplicated labor, advancing maternal age is associated with a progressively higher likelihood of interventions.
• The findings suggest that age-related changes in uterine function begin earlier than previously recognized.