Baseline characteristics for randomized versus non-randomized participants.

Data are presented as number (percent) unless otherwise indicated.aPercents given are related to available data per characteristic and may differ from the total number of patients.bPercents given as part of known educational level.cOutcome characteristic with more than 5% missing data. Education: data available for 425 women (58%); body mass index at booking: data available for 616 women (83%); body mass index at start study available for 346 women (47%); maternal temperature at inclusion: data available for 689 women (93%).