Restless Leg Syndrome Affects 1 in 4 Women During Pregnancy

A quarter of women who are pregnant meet the diagnostic criteria for restless leg syndrome (RLS) during pregnancy and a fifth of pregnant women with RLS qualify for pharmacologic interventions for sleep disorder, according to study results presented at the 2025 Annual Meeting of the American Academy of Sleep Medicine and the Sleep Research Society, held from June 7 to 11 in Seattle, Washington.

Pregnancy is an established risk factor for RLS, however, the impact of RLS on pregnancy and postpartum and trends in severity are poorly understood.

Researchers from the Regional Hospital of Lugano and Neurocenter of Southern Switzerland in Switzerland sourced data for this analysis from the Life-ON Cohort Study, which was a multicenter study.

Pregnant women (N=439) were recruited at 10 to 15 weeks’ gestation and evaluated for the presence of the 5 RLS criteria, defined by the International RLS Study Group, and scored using the International RLS Study Group Rating Scale (IRLS) at 11 follow-up visits. The participants also underwent a polysomnography during their second trimester.

The primary outcomes of this analysis were the prevalence of RLS, the trajectory of RLS during pregnancy, and risk factors for RLS in pregnancy. Severe or very severe RLS was defined as an IRLS score greater than 20 points.

A total of 26.03% of women met the diagnostic criteria of RLS.

Of women reporting RLS, 50.68% had evidence of RLS prior to pregnancy in their medical records (odds ratio [OR], 2.717; 95% CI, 1.791-3.782) and 18.7% had a family history of RLS.

The cumulative incidence of RLS during the entire pregnancy was 34.7%.

Severe RLS was observed among approximately 20% of women.

The predictors for RLS in pregnancy were previous RLS (hazard ratio [HR], 7.86; 95% CI, 4.09-15.07; P <.0001) and a history of depression (HR, 2.03; 95% CI, 1.003-4.09; P =.049). Family history of RLS tended to be associated with RLS risk in pregnancy (HR, 2.00; 95% CI, 0.92-4.35; P =.08).

“RLS is a highly frequent complaint during pregnancy, with women who have a positive personal or family history for RLS being especially predisposed to develop manifest symptoms. The symptom severity remains relatively stable across pregnancy with a significant proportion (20%) warranting evaluation for a specific pharmacologic treatment. A screening approach and treatment of eligible women could greatly improve quality of life and reduce comorbidity during pregnancy,” the researchers concluded.