Transient RLS during pregnancy is a risk factor for the chronic idiopathic form.

OBJECTIVE: Pregnancy is a risk factor for transient restless legs syndrome, which usually recovers during the postdelivery period. The goal of the present survey is to investigate whether restless legs syndrome during pregnancy represents a risk factor for later development of restless legs syndrome.

METHODS: A long-term follow-up study, planned as an extension of a previous survey on restless legs syndrome during pregnancy, was carried out. After a mean interval of 6.5 years, 207 parous women were contacted again to compare the incidence of restless legs syndrome among subjects who never experienced the symptoms with those who reported restless legs syndrome during the previously investigated pregnancy.

RESULTS: Seventy-four women who experienced restless legs syndrome during previous pregnancy, and 133 who did not, were included in the study. The incidence of restless legs syndrome was 56% person/year in women who experienced the transient pregnancy restless legs syndrome form, and 12.6% person/year in subjects who did not, with a significant 4-fold increased risk of developing chronic restless legs syndrome in women who presented restless legs in the previous pregnancy. Considering further new pregnancies during the follow-up period, the restless legs symptoms reappeared in 58% of the cases, while they emerged for the first time in only 3% of women who had never experienced restless legs syndrome.

CONCLUSIONS: The transient pregnancy restless legs syndrome form is a significant risk factor for the development of a future chronic idiopathic restless legs syndrome form, and for a new transient symptomatology in a future pregnancy.