While often temporary, pregnancy leg cramps can stop you in your tracks, especially until they pass. The good news? There are ways to minimize the intensity and frequency of these spasms and prevent them from happening in the first place.  To get to the bottom of leg cramps, Verywell asked three OB/GYNs to share insight on the causes and symptoms of leg cramps, how to prevent them, and what you can do to feel better when you experience leg cramps during pregnancy. 

Why Do Leg Cramps Occur During Pregnancy?

Although no one knows the exact cause of leg cramps during pregnancy, any mom-to-be who experiences them will tell you they are a painful symptom of pregnancy, especially in the second and third trimester.  Rachel Adams, MD, OB/GYN at Mercy Medical Center, says a build-up of a substance called lactic acid in the muscle is another possible cause of legs cramps during pregnancy. Another reason for leg cramps, says Adams, is the presence of a blood clot. “It can present similar to harmless leg cramps, but they are much more dangerous,” she says. If you’re experiencing leg cramps with swelling of one leg greater than the other, Adams says this can be the sign of a blood clot, and you should immediately contact your doctor. Leg cramps can also be associated with imbalances in electrolytes. Carolyn Cokes, MD, OB/GYN at Mercy Medical Center, says this can cause involuntary muscle contractions that can be anywhere from mild to quite painful.  In some circumstances, Cokes says some pregnant moms-to-be can have a version of restless leg syndrome, which has an additional range of possible underlying causes. “Women who have pre-existing restless leg syndrome typically have a worsening of their symptoms, especially in the third trimester,” she says.  Sherry Ross, MD, OB/GYN and Women’s Health Expert at Providence Saint John’s Health Center, says a few additional causes of leg cramps could be blood flow changes and carrying additional weight as the pregnancy progresses.

Symptoms of Leg Cramps

The symptoms of leg cramps depend on what is causing them. Typically, you will feel leg cramps in your calf muscles, but they may radiate up the leg. If the muscle is contracting involuntarily, Cokes says they can be quite painful and might wake you from sleep. “They often feel like your leg is immobilized or has a ‘knot’ from which the pain is emerging,” she says.  That said, they can also be mild twitches or feel like something is crawling on you. In some cases, Cokes says it may feel like you need to move your legs, but this is more typical of restless leg syndrome. Ross says they can feel like a sudden, sharp, and stabbing pain in the back of the calf. “At times, you can see or feel a hard and protruding lump on the back of the calf,” she says. 

How Are Leg Cramps Treated?

Treatment and prevention are important in the management of leg cramps. The good news is many of the protocols are the same for both stopping leg cramps in their tracks and preventing them from happening in the first place.  If you’re experiencing a leg cramp, Ross says to straighten out the cramping leg, with the heel outstretched first. Flex your ankle and toes back toward the shins, then wiggle the toes and gently massage the calf muscle.

Follow a Stretching Routine

To minimize leg cramps, follow a regular stretching routine. If possible, aim to stretch your legs daily, with an emphasis on your calves before going to bed. The standing calf stretch is a great place to start. 

Stay Physically Active

In addition to stretching three or more days a week, staying physically active with pregnancy-approved workouts can help prevent leg cramps. Low-impact cardiovascular exercises such as walking and swimming are excellent ways to raise your heart rate, get the blood flowing, and keep your muscles in shape. If you can, try to walk daily, unless your doctor has advised against it. 

Move Around Frequently

Avoid standing or sitting in one position for too long. Unless your doctor has you on bed rest, get up frequently, and move around. This is also a good time to do a few calf stretches. And when sitting, avoid crossing your legs. 

Drink Plenty of Water

Staying hydrated throughout the day can also keep leg cramps away. The American College of Obstetricians and Gynecologists (ACOG) recommends drinking 8 to 12 cups (64 to 96 ounces) of water every day during pregnancy. Ideally, spread your intake throughout the day, but limit the amount you drink before bed. 

Use Heat Therapy 

Warm showers and baths, especially before bed, can help treat leg cramps during pregnancy. You can also try a hot compress by placing a hot water bottle or a warm towel on the calf to ease the discomfort.

Wear the Right Footwear

Pregnancy is not the time for flip-flops or high heels. If possible, wear shoes that are supportive, secure, and provide cushioning. Plus, choose a shoe that is roomy enough to allow for swelling—something that is common during pregnancy. 

Other Considerations

If the leg cramps are involuntary muscle contractions, Cokes says magnesium supplementation may help. And for restless leg syndrome, she says a doctor needs to do a work-up to determine possible underlying triggers, such as low ferritin. Many medications used in pregnancy can also trigger a form of restless leg syndrome.

A Word From Verywell

Leg cramps during pregnancy are common. While they can be painful, most cramps are not harmful. If interventions such as stretching, staying hydrated, and exercising do not reduce the intensity or frequency of leg cramps, it might be time to call your doctor. Additionally, if your leg cramps get worse or are accompanied by redness, swelling, or warmth, contact your doctor immediately to make sure it is normal pregnancy leg cramps, and not something more serious.