Premenstrual syndrome (PMS) is the name of a group of symptoms that start 7 to 14 days before your period (menstruation). The symptoms usually stop soon after your period begins. Most women who have menstrual periods experience some premenstrual symptoms. About 40 percent of menstruating women have premenstrual syndrome, and 10 percent have severe symptoms.

Most women feel some discomfort before their periods. But if you have PMS, you may feel so anxious, depressed or uncomfortable that you can't cope at home or at work. Your symptoms may be worse some months and better others.

According to the American Journal of Psychiatry, "cyclic occurrences of symptoms that are of sufficient severity to interfere with some aspects of life, prior to menses, is PMS. Although definitions differ, some 150 symptoms may be associated with PMS.

Therefore, the most likely explanation for PMS is that many women are sensitive to the hormonal shifts that occur in the second half of the menstrual cycle.

The debated cause may range from hormonal imbalance to psychological and social factors. Patient Care, in reporting on the causes of PMS, states that "no clear cut differences have been found in the patterns, ratios, amounts, or timing of gonadal hormones in women with or without severe PMS."

How is PMS treated?

There is no cure for PMS, but eating a healthy diet, exercising regularly and taking medicine may help. Your doctor will talk to you about whether you need to change your diet and exercise habits. He or she may also prescribe medicine for you, depending on what your symptoms are.

You may need to try more than one medicine to find the treatment that works for you. Many medicines are available over-the-counter, but some require a doctor's prescription. Medicines that can be prescribed include diuretics, antidepressants and birth control pills. Other medicines for PMS are being studied.

The more a woman understands PMS, the more can be done.

Written by David Slade author of Mandarin English XL at