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Medical Author:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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In this Article

• Vaginal bleeding facts
• What is normal vaginal bleeding?
• What is abnormal vaginal bleeding?
• What conditions cause abnormal vaginal bleeding in women who are ovulating regularly?
• What conditions cause abnormal vaginal bleeding in women who are not ovulating regularly or vaginal bleeding after menopause?
• What causes abnormal vaginal bleeding during or after sexual intercourse?
• What causes abnormal vaginal bleeding during pregnancy?
• What tests are used to evaluate abnormal vaginal bleeding?
• How is irregular or abnormal vaginal bleeding treated?
• Find a local Obstetrician-Gynecologist in your town
• Vaginal Bleeding Index

Many conditions can interfere with the proper function of female hormones that are necessary for ovulation. For example, many conditions or circumstances may cause oligomenorrhea (reduction in the number of menstrual periods and/or amount of flow than usual) such as:

• If a woman has chronic medical illnesses or is under significant medical or emotional stress, she can begin to have a loss of her menstrual periods.
• Malfunction of a particular part of the brain, called the hypothalamus, can cause oligomenorrhea.
• Anorexia nervosa is an eating disorder associated with excessive thinness that causes many serious medical consequences as well as oligomenorrhea or amenorrhea (the absence of menstrual periods).
• Polycystic ovarian syndrome (PCO or POS) is a hormonal problem that causes women to have a variety of symptoms that include irregular or no menstrual periods, acne, obesity, infertility, and excessive hair growth; that are detectable with blood tests.

The complete loss of ovulation is referred to as anovulation. Since ovulation allows the body to maintain an adequate supply of progesterone, anovulation is a condition in which a woman's hormonal balance is tipped toward too much estrogen and not enough progesterone. The excess estrogen stimulates the growth of the lining of the uterus. The result is that the lining of the uterus becomes too thick, which eventually leads to an increased risk of uterine pre-cancer or uterine cancer over many years. In order to replace progesterone and establish a proper hormonal balance, doctors will prescribe either progesterone to be taken at regular intervals, or an oral contraceptive that contains progesterone. Such treatment dramatically decreases the risk of uterine cancer in women who do not ovulate. Because uterine cancer results from many years of anovulation, any woman with prolonged anovulation needs to be treated to avoid developing uterine cancer.

Women who are postmenopausal (those who have not had a menstrual period for 12 consecutive months or more) should not experience vaginal bleeding. Any vaginal bleeding is considered abnormal in postmenopausal women. Women who are taking combined estrogen and progesterone hormone therapy (HRT or HT) may experience some light, irregular vaginal bleeding during the first six months of treatment. Likewise, postmenopausal women who are taking a cyclic hormone regimen (oral estrogen and a progestin for 10-12 days per month) may experience some vaginal bleeding that is similar to a menstrual period for a few days each month.

Postmenopausal women who experience heavy or prolonged vaginal bleeding while on hormone therapy should always see a doctor to rule out more serious causes of vaginal bleeding. Less frequent but serious causes of vaginal bleeding in postmenopausal women include endometrial cancer or hyperplasia (overgrowth of the lining tissues of the uterus, which can be precancerous in some cases).