The exact cause of PMS is not known. However, factors such as disturbances in the levels of hormones such as progesterone, estrogen and prolactin during menstruation, vitamin B₆ deficiency and hypoglycemia (decrease in blood sugar) have been attributed to cause the syndrome. Social and personal issues relating to menstruation and womanhood may affect the psychological status of women thereby resulting in the symptoms of stress and depression in some. Daughters of women who were themselves PMS sufferers tend to suffer from PMS more commonly. ¹