Planned birth in the 39th week of pregnancy reduces perinatal mortality compared with expectant management even among low-risk women, a major study shows.

In findings at odds with prevailing concern about caesarean section rates, the researchers found that C-sections were associated with fewer adverse events than labour induction.

The University of Queensland’s Mater Research Institute and UK colleagues analysed data on nearly half a million low-risk pregnancies across two decades to compare outcomes for planned births at 39 weeks’ gestation versus continuing pregnancy into the 40th week.

Overall, planned birth in the 39th week was associated with half the odds of perinatal mortality, 62% lower odds of antepartum stillbirth and 84% lower odds of intrapartum stillbirth compared with expectant management, they found.