Restless Legs Syndrome and Sleep-Wake Disturbances in Pregnancy

Study objectives: To estimate the association of restless legs syndrome (RLS) and its frequency with sleep-wake disturbances in pregnancy.

Methods: A cohort of 1,563 women in their third trimester of pregnancy were recruited from prenatal clinics between March 2007 and December 2010. Demographic, pregnancy, and delivery data were extracted from medical records and sleep information was collected with questionnaires. To diagnose RLS, we used standardized criteria of RLS symptoms and frequency that were developed by the International Restless Legs Study Group. Logistic regression models were constructed to investigate the association of RLS and its frequency with sleep-wake disturbances (poor sleep quality, daytime sleepiness, poor daytime function) and delivery outcomes.

Results: Overall 36% of the pregnant women had RLS, and half had moderate to severe symptoms. Compared to women without RLS, those with RLS were more likely to have poor sleep quality (odds ratio [OR] 2.2, 95% confidence interval [CI] 1.7-2.9), poor daytime function (OR 1.9, 95% CI 1.4-2.4), and excessive daytime sleepiness (OR 1.6, 95% CI 1.3-2.0). A dose-response relationship also was evident between RLS frequency and each of the sleep-wake disturbances. There was no evidence for any association between RLS and delivery outcomes.

Conclusions: RLS is a significant contributor to poor sleep quality, daytime sleepiness, and poor daytime function, all common and often debilitating conditions in pregnancy. Obstetric health care providers should be aware of these associations and screen women for RLS.

Commentary: A commentary on this article appears in this issue on page 857.