Optimising the outcomes of induction of labour through robust evidence. 1. Induction of labour in the third trimester: an individual participant data meta-analysis of randomised controlled trials to re-evaluate the timing of induction of labour.

Induction of labour is carried out when the risks of advancing gestation outweigh maternal and foetal benefits. It is one of the most frequent obstetric interventions, accounting for nearly one-fourth of all births in high-income countries and generally lower rates in low- and middle-income countries. Recent rates of labour induction have been reported to be as high as 34% in the UK, 23% in the USA, and 25-35% in Australia. This rate will likely rise further due to evidence from the recent ARRIVE trial. The body of evidence is still growing. The goal is to find a method that can mimic the natural, spontaneous onset of labour with equal or higher maternal satisfaction and prioritise the seemingly less-medicated methods, putting safety first. There should be more room for client satisfaction, specifically evaluated in qualitative studies. Attention should also be given to the practical, cost-effective methods in low- and middle-income countries as they bear a significant portion of the global maternal and perinatal morbidity and mortality. - Induction of labour at 41+0 gestational weeks or expectant management until 42 weeks - Induction of labour at 37 weeks or expectant management until 42 weeks - Induction of labour at 39 weeks or expectant management until 42 weeks Maternal and perinatal adverse outcomes tend to increase in term pregnancy as gestational age increases, becoming especially evident post-term. Management practices of late—and post-term pregnancies are diverse in different settings globally, and the optimal time point for intervention by labour induction is yet to be determined. As there are a number of new randomised controlled trials on this topic, it is worth studying in a large individual participant database. This will also be an update of the Cochrane review using individual participant data and a trustworthiness assessment.