Indications for Induction of Labour

Prolonged pregnancy

An ultrasound to confirm gestation should be offered before 20 weeks of gestation, as this reduces the need for induction for perceived post-term pregnancy. Women with uncomplicated pregnancies should be offered induction of labour beyond 41 weeks.

From 42 weeks, women who decline induction of labour should be offered increased antenatal monitoring consisting of a twice weekly CTG and ultrasound estimation of maximum amniotic pool depth.

Population studies indicate that, in women who are healthy and have otherwise uncomplicated pregnancies, perinatal mortality and morbidity is increased in pregnancies of more than 42 weeks. The risk of stillbirth increases from one per 3000 continuing pregnancies at 37 weeks to three per 3000 continuing pregnancies at 42 weeks to six per 3000 continuing pregnancies at 43 weeks. A similar increase in neonatal mortality is also reported.

Diabetes in pregnancy

Women who have pregnancies complicated by diabetes should be offered induction of labour prior to their estimated date for delivery. Induction of labour of term pregnancies in women with diabetes is associated with a reduced risk of macrosomia.

Prelabour rupture of the?membranes

Women with prelabour rupture of the membranes at term (over 37 weeks) should be offered a choice of immediate induction of labour or expectant management. Expectant management of women with prelabour rupture of the membranes at term should not exceed 96 hours following membrane rupture.

There is no difference in operative delivery rates between induction versus a conservative approach in women with prelabour rupture of the membranes.

A policy of induction of labour is associated with a reduction in infective sequelae for mother and baby.⁰⁰⁰¹

Maternal request prior to 41 weeks.

Where resources allow, maternal request for induction of labour should be considered when there are compelling psychological or social reasons and the woman has a favourable cervix.

The risks of induction of labour for the mother will be equivalent to those of the general population. However, any potential benefits accrued are less easy to quantify. There is an increased risk of respiratory distress syndrome in the baby if labour is induced before term. Therefore, it is important that these risks are highlighted in any discussions regarding induction prior to term. There is insufficient evidence to allow comment on the risks associated with elective induction of labour for maternal request.