One-in-two hypertensive pregnant women who habitually snore (three or more nights per week) may have unrecognized obstructive sleep apnea (OSA), according to a new University of Michigan-led research study.

In addition, one-in-four hypertensive pregnant women who don’t snore also unknowingly suffer from OSA, according to the study that appears in the British Journal of Obstetrics and Gynecology.

“Our findings show that a substantial proportion of hypertensive pregnant women have obstructive sleep apnea and that habitual snoring may be one of the most telling signs to identify this risk early in order to improve health outcomes,”┬ásaid lead author Louise O’Brien, PhD, MS, associate professor at Univ of Michigan’s Sleep Disorders Center.

“We know that habitual snoring is linked with poor pregnancy outcomes for both mother and child, including increased risk of C-sections and smaller babies.”