Period Cramps: What’s Normal, What Helps and When It Could Be Endometriosis

Most period pain is common and treatable at home. Learn what helps fastest, which pain is not normal, and the signs that point to endometriosis or another cause.

The short answer

Mild to moderate cramps in the first one to three days of a period are common. They are caused by prostaglandins, chemicals that make the uterus contract to shed its lining. Anti-inflammatory painkillers such as ibuprofen or naproxen, heat and gentle movement help most people. Pain that stops you working or sleeping, gets worse each year, or happens outside your period is not something you should just put up with.

Why periods hurt

Before a period, the lining of the uterus releases prostaglandins. Higher levels cause stronger contractions, less blood flow to the muscle and more pain. This is called primary dysmenorrhoea: painful periods without an underlying condition. It usually starts within a few years of the first period and often eases with age or after pregnancy.

Secondary dysmenorrhoea is pain caused by something else, such as endometriosis, adenomyosis, fibroids or pelvic infection. It often starts later, lasts longer than the bleeding, or changes in pattern.

What actually helps

• NSAIDs taken early. Ibuprofen or naproxen lower prostaglandins. They work best started at the first sign of pain or bleeding and taken regularly for a day or two, as the label directs. Check with a pharmacist if you have asthma, stomach ulcers, kidney problems or are on blood thinners.
• Heat. A heat pad or hot water bottle on the lower belly or back relaxes the muscle and works about as well as some painkillers for many people.
• Movement. Walking, stretching or yoga can ease pain, even though resting can feel more tempting.
• Hormonal contraception. The pill, patch, ring, hormonal IUD or implant can make periods lighter and less painful. Discuss options with a doctor or nurse.
• TENS. A small pulse unit placed on the skin helps some people.

What is not normal

See a doctor if any of these apply:

• Pain that is not helped by painkillers or makes you miss school, work or plans
• Pain that has become worse over months or years
• Pain during or after sex, with bowel movements or when you pee
• Pain between periods or bleeding between periods
• Very heavy bleeding (see our guide to heavy periods)
• Trouble getting pregnant

Seek urgent care for sudden severe pelvic pain, pain with fever, fainting, or pain with a positive pregnancy test.

Could it be endometriosis?

Endometriosis is when tissue similar to the lining of the uterus grows elsewhere, usually in the pelvis. It affects about 1 in 10 women of reproductive age, and diagnosis often takes years because severe period pain is dismissed as normal. Common signs include period pain that painkillers don’t control, pain with sex, painful bowel movements or peeing during periods, tiredness and difficulty getting pregnant. A doctor may start treatment based on symptoms; an ultrasound or MRI can help, and laparoscopy can confirm it.

Track it before your appointment

Note the days of pain, a 0–10 score, what you took and whether it helped, plus bleeding amount and any pain with sex or the toilet. Two or three cycles of notes make it much easier for a clinician to tell common cramps from something that needs investigation.

Frequently asked questions