Dysfunctional uterine bleeding, also called anovulatory bleeding, is any bleeding from the vagina that varies from a woman's normal menstrual cycle. The normal cycle is triggered by signals from hormones. Dysfunctional uterine bleeding occurs when the cycle's hormonal signals get thrown off. This can include alternating periods that are heavy and light, spotting or unpredictable shorter and longer cycles.
Regular monthly menstrual cycles flush out the endometrial lining, which is the blood-enriched layer of tissue that grows inside the uterus every month in anticipation of a possible pregnancy.
If ovulation does not occur, periods can be delayed, which allows the lining to grow thicker. For this reason, delayed periods are often heavy ones.
Lighter periods, or spotting between periods, may represent an endometrial lining that is unstable and leaking, either because hormonal levels don't adequately support it or because the lining may be too thick.
Other factors that can change bleeding patterns include:
- Hormonal abnormalities (thyroid problems, elevated prolactin hormone)
- Excessive exercise or weight loss
- Stress or illness
- The start of menstruation in adolescence. Regular ovulatory cycles may not develop for a few months or even years.
- The end of menstruation. Dysfunctional uterine bleeding is common in the months to years before menopause.
Irregular bleeding can come at different times from month to month and last for different lengths of time. The amount of blood flow may vary from light to extremely heavy with large clots. In some people, the bleeding may be associated with uterine cramps.
Your doctor will ask about your medical history and about symptoms that might suggest a cause for the irregular bleeding or other hormonal abnormalities. The doctor may do various tests to check for these causes of abnormal bleeding patterns:
- Pregnancy -- Urine or blood tests
- Thyroid hormone and prolactin hormone abnormalities -- Blood tests
- Menopause (especially in women in their 40s or 50s) -- Blood tests to determine if estrogen levels are falling, which suggests the beginning stages of menopause
- Abnormalities of the uterus or ovaries -- A transvaginal ultrasound, in which a small, rodlike probe is inserted into the vagina to take measurements of the endometrial lining
- Possible cancer in women over 35; or those who have had breast, ovarian or colon cancer; or who have a strong family history of these cancers; or who have not had a period in six months -- An endometrial biopsy, done in the office, in which the doctor uses a speculum to look at the cervix, then inserts a thin, straw-like tube through the cervix into the uterus, and brushes it along the endometrial layer to collect a tissue sample
If you have heavy bleeding, your doctor will check iron levels in your blood to see if you are anemic.
Most women have a period that is irregular in timing or in the amount of bleeding at some point during their menstrual years, most often because of a cycle without a normal ovulation. Normal periods may resume as early as the next period or might take a few months to become regular again. Some women become regular only with the help of treatments, such as birth control pills. If irregular periods signal the beginning of menopause, the last period may not occur for a few months or a few years.
There is no way to prevent dysfunctional uterine bleeding. See a doctor promptly if you continue to have irregular periods. Early diagnosis and treatment can help to make your periods regular again, which is important for your overall health.
If the cause of dysfunctional uterine bleeding is another medical condition, treating that condition should restore normal cycles. Otherwise, treatment is based on the cause, the amount of bleeding and the woman's reproductive goals (whether she wants to have children or not).
Birth control pills, which combine the hormones estrogen and progesterone, can regulate and decrease the amount of bleeding. Your doctor may recommend that you take monthly pills containing progesterone only. Women seeking to become pregnant may be treated with medications to help their ovaries ovulate more regularly.
Heavy bleeding can be stopped with higher doses of hormone pills, either estrogen or progesterone. When bleeding is more severe, hospitalization may be necessary. If hormonal therapy does not work, a surgical D and C (dilation and curettage) can stop severe cases of bleeding. During this procedure, the tissue lining of the uterus is removed, allowing a healthier lining to take its place.
If an endometrial biopsy reveals endometrial hyperplasia, which is a thicker and abnormal looking lining, closer monitoring with treatment may be required, especially in older women and postmenopausal women on hormone replacement therapy. Endometrial hyperplasia increases a woman's risk of developing endometrial cancer.
Call your doctor right away for an evaluation if you are having fevers, abdominal pain or heavy bleeding with dizziness or fainting.
If your periods are irregular over a few months, make an appointment to see your doctor. Be prepared to tell your doctor the dates of your last few periods.
There are many effective treatments to help regulate periods and control irregular bleeding. If you have irregular periods and are having difficulty becoming pregnant, you can take drugs that stimulate ovulation. Having irregular periods, however, does not mean you are infertile. You still need to use protection against pregnancy when you are sexually active.
National Women's Health Information Center (NWHIC)
8550 Arlington Blvd.
Fairfax, VA 22031