menstruation
If one or more of the symptoms you experience before or during your period causes a problem, you may have a menstrual cycle “disorder.” These include:

1. abnormal uterine bleeding (AUB), which may include heavy menstrual bleeding, no menstrual bleeding (amenorrhea) or bleeding between periods (irregular menstrual bleeding)
2. dysmenorrhea (painful menstrual periods)
3. premenstrual syndrome (PMS)
4. premenstrual dysphonic disorder (PMDD)

Heavy menstrual bleeding
One in five women bleed so heavily during their periods that they have to put their normal lives on hold just to deal with the heavy blood flow.

Bleeding is considered heavy if it interferes with normal activities. Blood loss during a normal menstrual period is about 5 tablespoons, but if you have heavy menstrual bleeding, you may bleed as much as 10 to 25 times that amount each month. You may have to change a tampon or pad every hour, for example, instead of three or four times a day.

Heavy menstrual bleeding can be common at various stages of your life—during your teen years when you first begin to menstruate and in your late 40s or early 50s, as you get closer to menopause.

Amenorrhea
You may also have experienced the opposite problem of heavy menstrual bleeding—no menstrual periods at all. This condition, called amenorrhea, or the absence of menstruation, is normal before puberty, after menopause and during pregnancy. If you don’t have a monthly period and don’t fit into one of these categories, then you need to discuss your condition with your health care professional.

Severe menstrual cramps (dysmenorrhea)
Most women have experienced menstrual cramps before or during their period at some point in their lives. For some, it’s part of the regular monthly routine. But if your cramps are especially painful and persistent, this is called dysmenorrhea, and you should consult your health care professional.

Premenstrual syndrome (PMS)
PMS is a term commonly used to describe a wide variety of physical and psychological symptoms associated with the menstrual cycle. About 30 to 40 percent of women experience symptoms severe enough to disrupt their lifestyles. PMS symptoms are more severe and disruptive than the typical mild premenstrual symptoms that as many as 75 percent of all women experience.

Premenstrual Dysphoric Disorder (PMDD)
Premenstrual dysphoric disorder is far more severe than the typical PMS. Women who experience PMDD (about 3 to 8 percent of all women) say it significantly interferes with their lives. Experts equate the difference between PMS and PMDD to the difference between a mild tension headache and a migraine.