Daytime sleepiness in pregnant women may indicate underlying breathing difficulties during sleep that could put them at higher risk of an emergency birth intervention, says an Australian study.

Women scoring higher than 11 on the Epworth Sleepiness Scale were less likely to have a spontaneous vaginal delivery and more than twice as likely to have an operative or instrumental birth due to fetal compromise, it showed.

The study of 178 women with uncomplicated pregnancies and BMI in the normal range was the first to show these associations, the University of Queensland researchers wrote.

Among the cohort, who all gave birth at the Mater Mothers’ Hospital in Brisbane, 43 had an emergency caesarean, 40 had instrumental deliveries and 95 had spontaneous vaginal deliveries.