Factors influencing delivery mode for nulliparous women with a singleton pregnancy and cephalic presentation during a 17-year period.

Objective: To evaluate the effects of maternal age, induction of labour, epidural analgesia and birth weight on mode of delivery in nulliparous women with a singleton pregnancy and cephalic presentation at > or =36 weeks gestation, and to describe how these factors and their influence have changed over a 17-year period from 1989 to 2005.

Study Design: The study was conducted in the obstetric department of a university teaching hospital in Ireland. Of 45,647 women delivered, 14,867 were nulliparous with a singleton pregnancy and cephalic presentation and undergoing labour at > or =36 weeks gestation, and were included in the study.