Restless Leg Syndrome

What Causes RLS?

Researchers have not been able to determine what causes RLS, but research is ongoing into causes ranging from genetics to mineral imbalances. It's the latter that is often suspected in pregnancy.

Georgianna Bell, executive director of the Restless Legs Syndrome Foundation, says some of the ongoing research is focusing on the role of iron in the brain. "Sometimes people will experience a form of secondary RLS and one of the causes can be very low iron in the blood," says Bell. "The symptoms are then resolved by taking iron supplements. There is also ongoing research studying the administration of iron intravenously. There does seem to be a connection—why it is more prevalent in pregnancy we just don't know."

Treatment Options

Dr. Becker agrees, noting that the first step in treatment of RLS is to make sure iron, ferritin, and folate levels are normal. If any of those appear low, they should be supplemented. He also suggests the following:

• Limit caffeine to early morning and preferably only one cup of coffee.
• Drink plenty of water.
• Try to fatigue the legs as little as possible. If you have a job where you're on your feet a lot, try to arrange to put your legs up more often.
• Counter stimuli. This can include support stockings, stretching exercises before bed, putting something at the foot of the bed that you can push against, and having your partner give you a massage.
• Water therapy. Stand in the shower and let the water hit you in the lower back and run down your legs. Some people prefer warm or hot water, some cold, or cool. Some people report that starting with hotter water and gradually moving it to cool also works to relieve the sensations. A warm bath is also a good idea and provides other positive benefits such as relaxation and distraction.
• Distraction. Try this when RLS occurs in resting situations that do not involve trying to sleep. Use whatever interests you: crossword puzzles, computer games, or any hobby or activity that will engage your attention.

For most people one of the above suggestions will work. For the one in 10 that Dr. Becker estimates won't find relief in these simple measures, it may be necessary to evaluate the risk/benefits of drug therapy. Because RLS generally is at its worst in the third trimester, many of the drugs used to treat it in non-pregnant persons will be safe to use during pregnancy. However, this is a decision to be made by the woman and her obstetrician.

The good news, according to Dr. Becker, is that RLS usually resolves itself once the baby is delivered. Then, he jokes, the real sleep disruptions begin.