Few women get away with no-pain periods, but there are now effective ways to minimise discomfort, explains Barbara Lantin

Painful periods were once thought to be entirely psychological. Because doctors could find no physical abnormality in patients, they assumed that the cause was all in the mind. Fortunately, we now know better.

There are two kinds of period pain or dysmenorrhoea: spasmodic and congestive. Their symptoms vary, but both are believed to be caused by hormone imbalances. The classic cramps in the lower abdomen are spasmodic dysmenorrhoea. The pain - in some cases as intense as labour pain - starts on the first day of the period and comes in waves about 20 minutes apart, each lasting around five minutes. It may be accompanied by sickness, headache and diarrhoea. By the third or fourth day, it has usually subsided.

During a period, chemicals in the body reduce the blood supply to the muscles of the womb in order to dislodge the lining. 'It seems that spasmodic dysmenorrhoea is caused by there being insufficient oestrogen for maturing and stretching the muscles of the womb,' says Dr Katharina Dalton, a pioneer in the treatment of pre-menstrual syndrome.

'During pregnancy there is an abundance of oestrogen for a full nine months and the muscle wall of the womb is stretched by the foetus. As a result, this type of period pain usually ends after pregnancy.'

Sufferers from congestive dysmenorrhoea experience a continuous, nagging pain in the lower abdomen and back which may start a week or more before the period, increase in severity on the first day of menstruation and then gradually ease. This kind of period pain does not disappear with pregnancy and may actually get worse. Stress can also exacerbate it. It may recur until periods cease with the menopause.

Research has shown that women who suffer from dysmenorrhoea have raised levels of certain hormone-like chemicals called prostaglandins that can trigger pain. Analgesics that reduce prostaglandin production such as mefenamic acid and ibuprofen can be beneficial.

If the pain becomes intolerable, your doctor may want to check that there is no underlying cause such as endometriosis or pelvic inflammatory disease. Once these have been ruled out, your GP may suggest the contraceptive pill which, because it suppresses ovulation and creates an artificial cycle, can be effective for treating spasmodic dysmenorrhoea. However according to Dr Dalton, the Pill is not useful for congestive dysmenorrhoea, which responds to progesterone, rather than oestrogen.

Many complementary therapies claim to be able to help reduce period pain, including reflexology, acupuncture and homeopathy, though strong scientific evidence is scarce. Changing your diet to block the production of pain-provoking prostaglandins may improve matters. Dr Penny Stanway, author of Natural Well Woman (Element, £12.99) suggests: 'The week before your period, choose foods rich in omega-3 essential fatty acids and monosaturated fatty acids, calcium, magnesium and vitamins C and E. Minimize your consumption of refined carbohydrates, animal protein, fat, alcohol and caffeine-containing drinks.'

Herbs that rebalance hormones can also be helpful. A survey carried out in 2000 by the American Pharmaceutical Association revealed that dong quai was the most popular herb for treating period pain. It is a natural painkiller and increases circulation to the womb. Black cohosh and vitex agnus castus are often recommended for menstrual problems, though again the scientific evidence is inconclusive.

If you are in the grip of cramps, try the herbs crampbark, black haw or skullcap. Take a deep bath to which you have added two drops of lavender oil and four of marjoram oil. Make a massage oil using two teaspoons of sweet almond oil plus three drops of an essential oil such as lavender, rose otto, or clary sage and rub gently over your abdomen. A hot pack or hot water bottle can also bring relief. Some women swear by a magnet - worn under your clothes in the area of the uterus - that claims to improve circulation and reduce spasm.

Although you may not feel like moving around, there is some evidence that exercise can alleviate period pains by increasing circulation to the pelvic region. Dr Stanway suggests kneeling on all fours and rocking your lower spine repeatedly up and down in a pelvic tilt. She also advises trying deep breathing exercises. Any treatment that you find relaxing is likely to bring some relief.