The effect of amniotomy on the outcome of spontaneous labour in uncomplicated pregnancy.

The objective of this study is to determine the effect of amniotomy on the outcome of spontaneous labour in uncomplicated pregnancy. A prospective randomised study of low-risk parous women with spontaneous onset of labour at term with singleton fetus in cephalic presentation and intact amniotic membranes and a cervical dilatation between 4 and 5 cm were randomly assigned to have amniotomy (Case) or no amniotomy (Control) during the course of labour. Maternal demographics, labour-delivery data and newborn outcome were compared. A total of 128 women were studied. The duration of labour was significantly shorter in the amniotomy group than the control group (208 vs 292 min; p < 0.05) with the only difference being in the first stage of labour. There was however no difference on the oxytocin requirement for labour augmentation, caesarean section rate, incidence of suspected fetal distress or instrumental delivery in both groups. Newborn outcome measured by Apgar scores at 1 and 5 min showed no significant difference. In conclusion, amniotomy significantly reduced the duration of the first stage of labour without affecting the oxytocin requirement, the rate of caesarean section and newborn outcome.