Painful Periods (Dysmenorrhoea)

Who gets painful periods?

Most women have some pain during periods. The pain is often mild, but in about 1 in 10 women the pain is severe enough to affect day-to-day activities.

• Primary dysmenorrhoea is the common type of painful periods. This is where there is no disease of the uterus (womb). It often occurs in teenagers and women in their 20's.
• Secondary dysmenorrhoea means that the pain is caused by a disease of the uterus. This is less common, and is more likely to occur in women in their 30's and 40's.

What causes the pain of primary dysmenorrhoea?
The cause is not clear. The uterus is normal and there is no disease of the uterus. What is thought to happen is that normal body chemicals called prostaglandins build up in the lining of the uterus. Prostaglandins help the uterus to squeeze (contract) and shed the lining of the uterus during a period. In women with period pain there seems to be a build up of too much prostaglandins, or the uterus may be extra sensitive to the prostaglandins. This may cause the uterus to contract too hard, which reduces the blood supply to the uterus. This can lead to pain.

What are the symptoms of primary dysmenorrhoea?
The main symptom is crampy pain in your lower abdomen. The pain:

• may spread to your lower back, or to the top of your legs.
• usually starts as the bleeding starts, but it may start up to a day before.
• usually lasts 12-24 hours, but lasts 2-3 days in some cases.
• can vary each period. Some periods are worse than others.
• tends to become less severe as you get older or after having a baby.

In some women, other symptoms occur during a period in addition to pain. For example: headaches, tiredness, faintness, breast tenderness, feeling sick, and diarrhoea.

What are the treatment options for primary dysmenorrhoea?

• Warmth. You may find it soothing to hold a hot water bottle against your lower abdomen, or to have a hot bath. The pain often does not last long, and this may be all that you need. (Be careful not to burn yourself with a hot water bottle which is too hot.)
   
• Paracetamol usually helps if the pain is mild.
   
• Anti-inflammatory painkillers greatly ease the pain in about 8 in 10 cases. They work by blocking the effect of the prostaglandin chemicals that are thought to cause the pain. Also, anti-inflammatories usually reduce the amount of bleeding. There are several types and brands, and most need a prescription. However, you can buy one type (ibuprofen) at pharmacies. Some tips when using an anti-inflammatory include the following.
  • Take the first dose as soon as your pain begins, or as soon as the bleeding starts, whichever comes first. Some doctors advise to start taking the tablets on the day before your period is due. This may prevent the pain from building up.
  • Take the tablets regularly, for 2-3 days each period, rather than 'now and then' when pain builds up.
  • Take a strong enough dose. If your pains are not eased, ask your doctor or pharmacist if the dose that you are taking is the maximum allowed. An increase in dose may be all that you need.
  • Some people cannot take anti-inflammatory painkillers. For example, people with a duodenal ulcer, and some people with asthma.
  • Side-effects are uncommon if you take an anti-inflammatory for just a few days at a time, during each period. (Read the leaflet that comes with the tablets for a full list of possible side-effects and cautions.)
     
• The combined oral contraceptive pill ('the pill') is an option if you also need contraception. Painful or heavy periods are much less likely if you take 'the pill'. This is because the pill causes the lining of the uterus to become thin, and the amount of prostaglandin is much reduced.
   
• A special intra-uterine contraceptive device called the IUS (intra-uterine system) is an option if you also need long-term contraception. This device slowly releases a progestogen hormone called levonorgestrel. This 'thins' the lining of the uterus. It is a good contraceptive, but also reduces the amount of pain and bleeding during periods.
   
• A TENS (transcutaneous electrical nerve stimulation) machine is an option for women who prefer not to use medication. These machines give out a small electrical current. They seem to work by interfering with pain signals which are sent to the brain from the nerves. However, you would normally have to buy a TENS machine as they are not usually available on the NHS for the treatment of period pain.
   
• Other treatments. If all other treatments have failed then various other medicines are sometimes tried. For example, medicines that prevent ovulation are sometimes used. These are not routine treatments as side-effects can be a problem, and the research evidence to support their use is limited.

A disease of the uterus (womb) sometimes causes painful periods. For example: endometriosis, fibroids, or infection of the uterus (pelvic infection). Symptoms tend to start several years after your periods first began. The following may indicate an underlying cause.

• If you have a change in your usual pattern of pain. For example, if your periods become more painful than they used to be, or the pain lasts longer than it used to. In some women with secondary dysmenorrhoea the pain starts several days before the period begins, and lasts all the way through the period. (This is uncommon with primary dysmenorrhoea.)
• If you have other symptoms. For example, irregular periods, bleeding in between periods, pains between periods, the bleeding becomes more heavy than previously, vaginal discharge, or pain during sex.

The treatment of secondary dysmenorrhoea depends on the underlying cause.

Some types of intrauterine contraceptive device (IUD) make painful periods worse in some women. The treatments for primary dysmenorrhoea (described above) often help. However, some women prefer to have their IUD removed if symptoms do not improve.

© EMIS and PIP 2006   Updated: January 2006   PRODIGY Validated

The authors and editors of this article are employed to create accurate and up to date content reflecting reliable research evidence, guidance and best clinical practice. They are free from any commercial conflicts of interest.

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