According to a study published online in Obstetrics & Gynecology, pregnant women diagnosed with sleep disorders are more likely to have a preterm birth than those without, Medscape reports.

“Women with an insomnia diagnosis had nearly twofold higher risk for an early preterm birth (less than 34 weeks of gestation) compared with women without a recorded sleep disorder diagnosis,” write Jennifer N. Felder, PhD, from the University of California, San Francisco, and colleagues. “The importance of these findings may be considerable given studies showing that more than 50% of pregnant women experience clinically significant insomnia.”

In addition, women with sleep apnea had a greater than twofold risk for preterm birth compared with those who did not have sleep apnea. According to the authors, recent data highlight a rising trend in preterm birth rates in the United States; preterm birth is the world’s number one killer of young children.