Prolonged pregnancy: balancing risks and interventions for post-term gestations

Abstract

Pregnancy that continues beyond 42 weeks of gestation (post-term) confers increased antepartum and intrapartum fetal risk. Maternal risk may also be associated with post-term pregnancy, for example increased likelihood of delivery via emergency Caesarean section. The increased likelihood of adverse perinatal outcomes associated with post-term pregnancy derives mainly from increasing fetal size and placental ageing. The key intervention currently available to manage the risks associated with prolonged pregnancy is to offer delivery. In the UK, induction of labour is routinely offered at 41 weeks. Although offering induction of labour to manage post-term pregnancy is intended to minimize risk, women should feel supported by healthcare professionals if they opt for expectant management or decline induction of labour.