Premenstrual syndrome (PMS) is a pattern of physical, emotional, and behavioral symptoms that appear before your menstrual period starts and disappear soon after bleeding begins.

PMS occurs only in women who ovulate during their monthly menstrual cycle. Women, who do not ovulate, such as pregnant women, women past menopause or women taking birth control pills, do not have PMS. If you are experiencing PMS and are not ovulating, you need to seek medical attention immediately.

Many women have normal, mild symptoms, such as cramps and mild breast tenderness, during their menstrual periods.

A diagnosis of PMS is reserved for symptoms that occur during the 2 weeks between ovulation and the first day of menstrual bleeding. PMS has a wide variety of psychological, behavioral and physical symptoms. Symptoms vary greatly from woman to woman and they may range from mild to severe.

PMS symptoms include:

Fatigue: This is the most common symptom of PMS. Women with PMS may feel so tired they can barely get through the day. Some women also may have trouble sleeping at night.

Tension/Irritability/Mood Swings: A woman with PMS may feel very on edge. Small annoyances seem huge. Often her response is out of proportion to the problem.

Difficulty concentrating: Many women with PMS find it hard to do things that require concentration, such as balancing a checkbook, following recipes, or making business decisions. They may also be forgetful.

Anger/Irritability: During PMS, normal feelings of anger are often exaggerated. A woman may be more argumentative and lash out at those around her.

Depression: Sadness and crying easily are common feelings related to PMS. At times the sadness may feel profound and inconsolable.

Food cravings: Some women crave particular foods, such as sweets or salt. Others find their appetite for almost any food increases.

Breast tenderness: Many woman experience swelling and soreness around their nipples or breasts.

Bloating/Water Retention in the abdomen, hands, and legs: Some women with PMS gain weight. Others have fluid shifts to the abdomen, hands, and legs that make them feel uncomfortably swollen or puffy.

Headaches: Duration and severity of headaches vary from woman to woman, but are common during PMS.

Weight Gain: Mostly due to water retention.

Acne: Some woman experience acne breakouts mostly in the facial area.