Period cramps happen because the uterus contracts to shed its lining during your period, and those contractions can be painful, especially when prostaglandins are high. Those chemicals also increase inflammation and make the cramps stronger.

Why it hurts

  • The uterus is a muscle, so when it squeezes, you can feel pain in the lower belly or back.
  • Higher prostaglandin levels usually mean stronger contractions and worse cramps.
  • Sometimes cramps are a sign of another condition, like endometriosis, fibroids, adenomyosis, pelvic inflammatory disease, or cervical stenosis.

When cramps are more concerning

Severe cramps, cramps that start later in life, pain between periods, or very heavy bleeding can suggest an underlying issue rather than typical period pain.

What can help

  • Heat on the lower belly or back.
  • An over-the-counter pain reliever like ibuprofen or naproxen, ideally taken early when cramps start.
  • Gentle exercise and rest.
  • A doctor’s visit if the pain is severe, unusual, or keeps happening.

In short: period cramps are usually caused by uterine contractions driven by prostaglandins, and they become worse when those signals are stronger.

Suggested meta description: Period cramps happen because the uterus contracts to shed its lining, and prostaglandins make those contractions more painful.
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