Factors associated with a prolonged second state of labour--a case-controlled study of 364 nulliparous labours.

The aim of the study is to identify factors associated with a second stage of labour greater than 2 hours in nulliparous women delivering at term. It a retrospective case-control study of 182 women with a second stage less than 2 hours' duration, matched with 182 women with a second stage greater than 2 hours. Women with a short second stage of labour were significantly younger (mean age 23.2 vs. 24.9 years) and had significantly smaller babies (mean weight 3315 g vs. 3463 g) than women with a long second stage. Long duration of the second stage of labour was significantly associated with oxytocin and epidural use. The intervention rate did not rise above 50% until the second stage exceeded 5 hours duration. The fetal outcome was good in both groups of patients.