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Quick Facts

Menstrual Cramps


The Manual's Editorial Staff

Last full review/revision Dec 2019| Content last modified Dec 2019
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What are menstrual cramps?

Menstruation is when you have your period. Menstrual cramps are pains in your lower belly that happen a few days before, during, or after your period.

  • Your pain may be crampy or sharp

  • The pain may reach from your lower belly to your lower back and down the backs of your legs

  • Getting enough sleep, exercising, and taking NSAIDs, such as ibuprofen, may help lessen your discomfort

There are 2 types of menstrual cramps:

  • Primary

  • Secondary

Primary menstrual cramps are the most common type. Such cramps:

  • Don’t have a specific cause

  • Usually start when you're a teenager

  • Often run in families

  • Usually become less severe as you get older or after having a baby

Secondary menstrual cramps:

  • Are caused by another health problem, such as fibroids

  • Usually start when you're an adult

What causes menstrual cramps?

Primary menstrual cramps may be caused by:

  • High levels of prostaglandins

Prostaglandins are chemicals your body makes. They make your uterus contract, and your nerve endings more sensitive to pain.

Secondary menstrual cramps are most often caused by health problems that affect your uterus such as:

  • Endometriosis: tissue (endometrium) that normally belongs inside your uterus grows outside your uterus

  • Fibroids: tumors (that are not cancer) in your uterus

  • Adenomyosis: the tissue in the lining of your uterus grows into the wall of your uterus, causing it to get bigger and swell during your periods

What are the symptoms of menstrual cramps?

The main symptom is:

  • A crampy or sharp pain in your lower belly—the pain may come and go, or be a dull, constant ache

You may also have:

  • Headache

  • Feeling sick to your stomach or throwing up

  • Constipation

  • Diarrhea

You're more likely to have severe symptoms if:

  • Your menstrual periods started at an early age

  • You have long, heavy periods

  • You smoke

  • You have family members with severe menstrual cramps

When should I go to a doctor for menstrual cramps?

Menstrual cramps are unpleasant but not dangerous. However, more serious medical problems sometimes cause pain in the lower belly.

Go to a doctor today if you have lower belly pain and any of these:

  • Severe pain that began suddenly

  • Constant pain

  • Pain that gets much worse when you touch your belly or when you walk

  • Fever or chills

  • A thick, white or yellow discharge (fluid) from your vagina

Go to a doctor within a few days if you have menstrual cramps that are worse than usual or last longer than usual. If you don’t have any of the above, call your doctor when you can.

How can doctors tell if I have menstrual cramps?

Doctors will suspect menstrual cramps based on your symptoms and an exam. To make certain there's no other cause for your symptoms, they may do one or more tests:

  • Pregnancy test

  • Ultrasound of your lower belly to see your ovaries, uterus, and cervix

  • If your doctor thinks you may have pelvic inflammatory disease, they’ll take a sample from your cervix with a cotton swab and test it for infections

Rarely, your doctor may need to do imaging tests, such as MRI, or use a viewing tube (hysteroscopy) to look inside your uterus.

How do doctors treat menstrual cramps?

If you have primary menstrual cramps, doctors will suggest ways to lessen your pain:

  • Get enough sleep

  • Exercise

  • Put a heating pad on your lower belly

  • Take NSAIDs (nonsteroidal anti-inflammatory drugs), such as ibuprofen a day or 2 before your period starts and the first 2 days of your period

  • Sometimes, take nutritional supplements such as omega-3 fatty acids, flaxseed, magnesium, vitamin E, zinc, and vitamin B1

If you still have pain, doctors may:

  • Give you birth control pills—these pills keep your ovaries from releasing an egg

  • Give you other hormone treatments

  • Try nerve pain medicines such as gabapentin

  • Suggest alternative treatments such as acupuncture

If your pain is very severe even with treatment, doctors may:

  • Do surgery to cut the nerves that send pain signals from your uterus to your brain

If you have secondary menstrual cramps, doctors will treat the health problem that’s causing your pain.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
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