Premenstrual Syndrome - Causes

It is not clearly understood what causes it, but the following factors may lead to PMS:

• Cyclic changes in hormones. It is observed that the symptoms of PMS increase and decrease with cyclical changes in hormonal fluctuations. Over a period of time, they reduce or disappear during pregnancy and menopause.
• Chemical changes in the brain. Fluctuating levels of a chemical called serotonin in the brain is believed to contribute to mood swings and depression, and can also worsen PMS. Insufficient or decreased levels of serotonin can cause premenstrual depression as well as sleeping problems and a craving for certain foods.