leg cramps.
last revised · reviewed 2026-07-05
Sudden, painful calf cramps — usually at night — affect around half of pregnant women, most often in the second and third trimesters. The exact cause is unclear, but stretching, hydration, and gentle daily exercise reduce how often they strike.
what it feels like
A sudden, intense, gripping pain in the calf (sometimes the foot or thigh) that wakes you from sleep, with the muscle visibly knotted and hard. The acute spasm lasts seconds to minutes, but the muscle can stay tender for a day afterwards.
why it happens
No single cause has been proven. The growing uterus alters circulation in the legs, leg muscles carry more weight and tire faster, and shifts in calcium and magnesium handling may play a role. Whatever the mechanism, cramps cluster at night and become more frequent as pregnancy advances.
what helps
- During a cramp: straighten the leg and flex the foot hard towards your shin — this releases the spasm fastest
- Stretch calves before bed each night: lean into a wall with the back leg straight and heel down
- Stay well hydrated across the day
- Gentle daily exercise — walking or swimming — improves circulation in the legs
- Massage the calf or apply a warm compress after the spasm releases
- Avoid pointing your toes when stretching in bed — it is a classic trigger
- Mention frequent cramps to your midwife; magnesium supplements help some women, but check before taking anything
when to call your midwife or doctor
- Pain, swelling, redness, or warmth in one calf that persists between cramps — this could be a blood clot (DVT) and needs urgent same-day assessment; call your midwife or doctor
- One leg noticeably more swollen than the other
- Cramps so frequent or severe they seriously disturb every night's sleep
- Leg pain when walking that eases at rest — mention it to your doctor
This page is general information, not a diagnosis. When in doubt, call — no midwife has ever minded a careful question.
common questions
Why do pregnancy leg cramps happen at night?
After a day of carrying extra weight, calf muscles are fatigued, circulation is slower when lying still, and pointing the toes during sleep can trigger the spasm. That combination makes the small hours the classic time for pregnancy cramps to strike.
How do I stop a leg cramp fast?
Straighten your knee and pull your toes firmly up towards your shin — flexing the foot stretches the cramping calf and releases the spasm quicker than anything else. Massaging the muscle and walking a few steps afterwards helps it settle.
How do I tell a cramp from a blood clot (DVT)?
A cramp is a sudden spasm that releases within minutes, leaving mild soreness. A DVT causes persistent pain, swelling, warmth, or redness in one calf that does not come and go. Pregnancy raises clot risk, so one-sided persistent calf pain or swelling needs same-day medical review — call your midwife or doctor.
read it in context
Leg cramps tends to show up around these weeks of pregnancy:
related symptoms
- Round ligament pain
Round ligament pain is a sharp, brief pain or pulling sensation in the lower belly or groin — usually one-sided — caused by the ligaments that support the uterus stretching as it grows.
- Bleeding gums
Swollen, tender gums that bleed when brushing affect the majority of pregnant women — pregnancy hormones increase blood flow to the gums and amplify their reaction to plaque.
- Headaches
Headaches are common in pregnancy, especially the first trimester, driven by hormone shifts, increased blood volume, tiredness, and often caffeine withdrawal.
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