Fact sheet: Period pains

Many women have painful cramps in their lower abdomen (tummy) during their monthly period, as well as other complaints such as headaches and general discomfort. Some women already experience symptoms such as cramps, headaches and breast tenderness in the days leading up to their period (premenstrual syndrome or PMS). This fact sheet is about the problems women have during their period, not before.

What happens during a menstrual period?

Throughout a woman’s reproductive years, between her first and last period (menopause), the mucous membranes lining the inside of the womb (uterus) build up every month. The lining of the womb is called the endometrium. It has a good blood supply and contains a lot of endometrial glands. Its function is to provide the embryo with nutrients if the woman becomes pregnant during one menstrual cycle. If she does not become pregnant, the lining of her womb is shed during her menstrual period (menstruation). A period usually lasts between three to five days in most women.

To shed the lining, the muscles of the womb tighten (contract) and relax in an irregular rhythm. This helps the tissue lining the womb to detach and flow out of the body through the neck of the womb and vagina. The muscle contractions are usually not noticeable or only cause mild discomfort. But some women regularly have strong and very painful contractions, known as menstrual cramps. They may only have pain in the lower abdomen area, but can also have back or leg pain. In some women, the cramps cause nausea, vomiting and/or diarrhea. The medical term for very painful periods is “dysmenorrhea”.

How common is strong period pain?

Painful menstruation is fairly common: about 3 out of 4 women have pain at some point during their period. The intensity of pain varies. One in 10 women has such bad pain that they are unable to carry out their usual daily activities on 1 to 3 days every month.

Younger women (under 20) tend to have worse period pains than older women. About 7 to 9 out of 10 teenage girls have moderate to severe period pains. The pain usually gets better or even disappears completely within a few years after their first period. Many women find that they have milder period pains after giving birth to their first child. Heavier periods are often associated with more intense pain. Some evidence suggests that smoking increases the risk of having period pains.

Could period pain be sign of an illness?

There are two types of period pain: primary and secondary. Period pain which is caused by menstrual cramps alone is called primary dysmenorrhea (or dysmenorrhoea). Pain which is caused by a medical condition is called secondary dysmenorrhea. Examples of such conditions include ovarian cysts (fluid-filled sacs), myomas (benign, non-cancerous growths, mainly found in the muscle layer of the womb) and endometriosis. In endometriosis, the endometrium grows outside of the womb, too. You can read more about endometriosis here. And here you can find information that can help you find out whether your period pain is normal or might be a sign of endometriosis. Sometimes contraceptive coils (IUDs: intrauterine devices) used for birth control can cause secondary dysmenorrhea.

Conditions such as cysts, myomas and endometriosis often remain unnoticed. However, they only need to be treated if they cause severe problems or if tissue starts sticking together (adhesions). This could lead to, for example, problems with the function of the ovaries or other organs. Menstrual pains that are very bad or become worse over time may be a sign of such tissue growths. In this case it would be good to see a doctor.

Generally speaking, primary and secondary dysmenorrhea does not only differ in terms of the severity of pain experienced, but also in terms of when they first occur. Primary dysmenorrhea usually first arises within six to twelve months after a woman’s first period, and lasts two to three days each month during menstruation. Secondary dysmenorrhea often first occurs after a woman has already been menstruating for several years. Here, women may also have pain at times of the month other than during menstruation.

What causes period pain?

It is not known why some women have painful periods and others do not. Certain hormone-like transmitters called prostaglandins probably play a role. Women who have period pains may produce too many prostaglandins or be particularly sensitive to them. Among other things, prostaglandins regulate smooth muscle contractions and influence pain perception. They also cause the muscles in the womb  to tighten, helping to shed the endometrial lining. During the contractions, the blood supply to the womb tissue is reduced. This might also cause pain.

Most medications that are used to treat period pains work by influencing the production of prostaglandins. The group of painkillers known as NSAIDs (non-steroidal anti-inflammatory drugs) blocks prostaglandins. The “pill” prevents ovulation (when an ovary releases a mature egg). If a woman does not ovulate, fewer prostaglandins are produced, the mucous membrane lining does not become as thick as usual, and she has a lighter period.

Doctors used to believe that period pains were mainly caused by emotional and psychological problems. However, it is now clear that there are physical causes. But the mental state of a woman may also have an influence on the production of prostaglandins. Eating habits or diets could play a role, too.

What can women do to relieve period pains?

There are many different medications and strategies that aim to reduce or prevent period pains. Some are only used during the monthly period itself, whereas others affect a woman’s whole menstrual cycle (eg the pill), lifestyle or diet. They work by

• targeting the cause of menstrual cramps (eg hormone production),
• decreasing pain and discomfort,
• influencing pain perception in the brain, and/or
• helping women to cope better with their symptoms.

Women receive a lot of, sometimes contradictory, advice about menstrual pain – from doctors, but also other women, friends, and their mothers and sisters. Some people say it is best to stay in bed until the pain goes away, whereas others suggest trying to go about your normal activities because staying in bed is likely to make you feel worse, physically and mentally. Unfortunately, there is not much scientific evidence about what approach is best. Many women try out several things to find out through trial and error what helps them the most. The different approaches include:

• methods which aim to relieve the cramping and pain. For example: movement, relaxation techniques and breathing exercises (eg yoga), applying heat (eg taking a warm bath, using a hot water bottle or heating pad, going to a sauna), a massage,
• painkillers (NSAIDs such as ibuprofen and diclofenac, paracetamol),
• hormonal substances such as progestin and estrogen, available in various combinations in the “pill” or in preparations containing only progestin (the “mini-pill”),
• psychological approaches used in pain management (e.g. behavior therapy for pain relief, biofeedback, breathing exercises, relaxation techniques),
• procedures which target pain stimulus, such as acupuncture, acupressure or TENS (transcutaneous electrical nerve stimulation),
• herbal medications and dietary supplements,
• special diets which aim to influence hormone production (for example, low-fat vegetarian food, a low-salt diet) or drinking more fluids,
• alternative approaches such as homeopathic or chiropractic treatment,
• surgery.

Which treatments help?

NSAID painkillers have been shown to effectively relieve menstrual pain. In the trials evaluated, 7 out of 10 women who took a placebo stayed at home due to their period pains. Of the women who took NSAIDs, only 3 out of 10 did not go to school or work. NSAIDs also most likely relieve pain somewhat better than paracetamol. You can read more about that here. Hormonal products like the “pill” have been shown to reduce pain too. There is weak evidence that taking fish oil, vitamin B or magnesium may help reduce menstrual pain. More research is needed in this area to be able to say for sure if they help. Surgery and chiropractic treatment have not been shown to be effective against menstrual pain so far. There have been some trials on acupuncture, but they have failed to produce evidence that it can reduce pain.

Taking NSAIDs may have adverse effects. The most common ones are stomach problems, nausea, vomiting, headaches and drowsiness. Women who use hormonal products may have adverse effects such as headaches or nausea too. Some herbal medications and dietary supplements are also known to have negative effects. If you would like to know more about the possible adverse effects and drug-drug interactions of alternative medications and treatments, click here.

Menstrual pain in young women often decreases or goes away over time. Yet if a woman has such bad pain that she is regularly unable to perform daily activities, it might help to see a doctor. He or she will be able to help to determine whether the pain is being caused by a condition such as endometriosis or another health problem, and to find the best treatment options.

You will find the most important information about endometriosis in our fact sheet.

Author: German Institute for Quality and Efficiency in Health Care (IQWiG)


Next planned update: February 2014. You can find out more about how our health information is updated here.

© IQWiG (Institute for Quality and Efficiency in Health Care)