Pregnant women who struggle to get seven or more hours of sleep per night could be more prone to gestational diabetes and are more likely to develop type 2 diabetes post-birth, a new study published in Sleep Medicine Reviews reports.

Women are already at risk for sleep deprivation when compared to their male counterparts, Sirimon Reutrakul, MD, CDE, and co-authors wrote in their paper, and are about 8 percent more likely to suffer from poor sleep than men. The discomfort, nausea, vomiting, urinary frequency and changes in progesterone levels that come with pregnancy can result in an increased risk for insufficient rest during all three trimesters, leading to progressively worse sleep over the duration of a pregnancy.

According to the National Sleep Foundation, 78 percent of women report more disturbed sleep during pregnancy than at any other time in their lives.

“While the amount of sleep considered to be adequate may differ among individuals, it has been recently recommended that adults aged 18 to 60 years should obtain seven or more hours of sleep per night on a regular basis to promote optimal health,” Reutrakul and co-authors wrote in their study. “However, guidelines on adequate sleep in pregnancy are lacking.”

Data exist that link lack of sleep in pregnant women and increased risks of preterm delivery and postpartum depression, but the connection between less sleep and an increased risk of gestational diabetes mellitus (GDM) is new and still tenuous.

In an effort to strengthen that evidence, Reutrakul and her team narrowed 559 studies, pulled from the Medline and Scopus databases, to a handful that examined the sleep habits of 17,308 pregnant women through both objective and subjective analysis. Doctors evaluated the mothers’ sleep quality through either objective measurements or self-reported data from the women themselves.

Reutrakul and colleagues found that short sleep duration in general was associated with a 1.7-fold increase in risk of GDM in pregnant women, while 6.25 hours per night or less resulted in a 2.84-fold increase in diabetes risk. These women also had higher one-hour glucose values, the authors wrote.

“Short sleep duration, both self-reported and objectively measured, was associated with hyperglycemia in pregnancy and an increased risk of GDM, although heterogeneity and risk of bias existed in the current analysis,” Reutrakul and co-authors wrote. “Future studies should explore the effects of sleep extension, as an adjunct to the standard care, on gestational diabetes risk and fetal outcomes.”

GDM is estimated to affect between 3.5 and 7.1 percent of all deliveries in the U.S., according to the research, and is typically diagnosed between 24 and 28 weeks of gestation. The condition, which commonly presents itself in women without any diabetic symptoms, can lead to a more than sevenfold increase in risk for developing type 2 diabetes after pregnancy. In addition, babies born to moms with GDM are statistically more prone to cardiometabolic problems, including diabetes and obesity.

These facts underline the necessity for further research on the subject, Reutrakul and colleagues wrote.

“Identifying risk factors for GDM may help in not only preventing GDM during pregnancy, but possibly improving future maternal and fetal health,” they said.