Leg Cramps in Pregnancy

Why are my legs cramping up so much? 

It’s most likely because your leg muscles are tired from carrying around extra weight. Leg cramps may start to plague you during your second trimester and get worse as your pregnancy progresses and your belly gets bigger. They may be aggravated by the pressure your expanding uterus puts on the blood vessels that return blood from your legs to your heart and the nerves leading from your trunk to your legs. While these cramps can occur during the day, you’ll probably notice them most at night.

You may have read that getting too little calcium and potassium can cause leg cramps, or that getting too much phosphorus (found in processed meat, snack foods, and soda) can have the same effect because it can keep you from absorbing enough calcium. But no good studies back up either of those theories. It’s a good idea, though, to make sure you’re getting enough calcium and potassium while you’re pregnant. If you don’t, your growing baby will leach what he needs from your bones, which can put you at higher risk for osteoporosis later. Be sure not to take calcium supplements that contain bone meal or dolomite, which can contain dangerous levels of lead. (In fact, don’t take any herbal or vitamin supplements without first discussing it with your healthcare provider.)

What can I do about these cramps?

Try these tips for keeping leg cramps at bay:

  • Avoid standing or sitting with your legs crossed for long periods of time.
  • Stretch your calf muscles (see below) regularly during the day and several times before you go to bed.
  • Rotate your ankles and wiggle your toes when you sit, eat dinner, or watch TV.
  • Take a walk every day, unless your midwife or doctor has advised you not to exercise.
  • Avoid getting too tired. Lie down on your left side to improve circulation in your legs.
  • Stay well-hydrated during the day by drinking water regularly.
  • Try a warm bath before bed to relax your muscles.

There’s some evidence that taking a magnesium supplement in addition to a prenatal vitamin may
have some benefits. But check with your provider before taking any kind of supplement during pregnancy.

If you do get a cramp, immediately stretch your calf muscles: Straighten your leg, heel first, and gently flex your toes back toward your shins. It might hurt at first, but it will ease the spasm and the pain will gradually go away. You can relax the cramp by massaging the muscle or warming it with a hot-water bottle. Walking around for a few minutes may help, too.

What if the pain persists?

If your muscle pain is constant and not just an occasional cramp, or if you notice swelling or tenderness in your leg, call your practitioner. In rare cases, a pregnant woman may develop a blood clot, which requires immediate medical attention.