Br J Obstet Gynaecol. 1994 Apr;101(4):307-9. doi: 10.1111/j.1471-0528.1994.tb13615.x.
To measure the effect of a policy of routine amniotomy on nulliparous labour.
A multicentre randomised controlled trial.
One thousand four hundred and sixty-three nulliparous women in spontaneous labour at term with intact membranes and a single cephalic fetus.
To have the membranes ruptured routinely early in labour or left intact for as long as possible.
Duration of labour, operative and instrumental delivery rates, use of analgesia, perinatal death, neonatal convulsions and admission to special care.
Median duration of labour was 8.4 h in the early rupture group and 9.4 h in the late group. There was no difference in caesarean section, typical odds ratio (OR) 1.1, 95% CI 0.65-1.8; operative vaginal delivery, OR 1.1, 95% CI 0.83-1.5; use of epidural/spinal, OR 0.92 95% CI 0.72-1.2; use of pethidine, OR 1.0, 95% CI 0.79-1.4; neither method of analgesia, OR 0.96, 95% CI 0.68-1.3; blood transfusion, OR 0.71, 95% CI 0.28-1.8. There was no effect on fetal intubation, OR 1.40 (95% CI 0.78-2.5); admission special care, OR 1.28 (95% CI 0.65-2.5). One fetus in the early amniotomy group had neonatal convulsions, but there were no perinatal deaths.