Effects of induction of labour versus expectant management in women with impending post-term pregnancies: the 41 week – 42 week dilemma

Joep C Kortekaas, Aafke Bruinsma, Judit KJ Keulen, Jeroen van Dillen, Martijn A Oudijk, Joost J Zwart, Jannet JH Bakker, Dokie de Bont, Marianne Nieuwenhuijze, Pien M Offerhaus, Anton H van Kaam, Frank Vandenbussche, Ben Willem J Mol, Esteriek de Miranda

Post-term pregnancy, a pregnancy exceeding 294 days or 42 completed weeks, is associated with increased perinatal morbidity and mortality and is considered a high-risk condition which requires specialist surveillance and induction of labour. However, there is uncertainty on the policy concerning the timing of induction for post-term pregnancy or impending post-term pregnancy, leading to practice variation between caregivers. Previous studies on induction at or beyond 41 weeks versus expectant management showed different results on perinatal outcome though conclusions in meta-analyses show a preference for induction at 41 weeks. However, interpretation of the results is hampered by the limited sample size of most trials and the heterogeneity in design. Most control groups had a policy of awaiting spontaneous onset of labour that went far beyond 42 weeks, which does not reflect usual care in The Netherlands where induction of labour at 42 weeks is the regular policy. Thus leaving the question unanswered if induction at 41 weeks results in better perinatal outcomes than expectant management until 42 weeks.