- Vaginal bleeding definition and 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 vaginal bleeding after menopause or abnormal vaginal bleeding in women who are not ovulating regularly?
- What causes abnormal vaginal bleeding during pregnancy?
- What causes vaginal bleeding during or after sexual intercourse?
- What diagnostic tests are used to evaluate abnormal vaginal bleeding?
- How is irregular vaginal bleeding treated?
Vaginal bleeding definition and facts
- Normal vaginal bleeding is the periodic blood flow from the uterus.
- Normal vaginal bleeding is also called menorrhea. The process by which menorrhea occurs is called menstruation.
- In order to determine whether bleeding is abnormal, and its cause, the doctor must answer three questions: Is the woman pregnant? What is the pattern of the bleeding? Is she ovulating?
- Abnormal vaginal bleeding in women who are ovulating regularly most commonly involves excessive, frequent, irregular, or decreased bleeding.
- May causes of abnormal vaginal bleeding are associated with irregular ovulation.
- A woman who has irregular menstrual periods requires a physical examination with a special emphasis on the thyroid, breast, and pelvic organs.
- Treatment for irregular vaginal bleeding depends on the underlying cause. After the cause is determined, the doctor decides if treatment is actually necessary.
What is normal vaginal bleeding?
Normal vaginal bleeding is the periodic blood that flows as a discharge from the woman's uterus. Normal (menstrual) vaginal bleeding is also called menorrhea. The process by which menorrhea occurs is called menstruation.
Normal vaginal bleeding occurs because of cyclic hormonal changes. The ovaries are the main source of female hormones, which control the development of female body characteristics such as the breasts, body shape, and body hair. The hormones also regulate the menstrual cycle. The ovary, or female gonad, is one of a pair of reproductive glands in women. They are located in the pelvis, one on each side of the uterus. Each ovary is about the size and shape of an almond. The ovaries produce eggs (ova) and female hormones. During each monthly menstrual cycle, an egg is released from one ovary. The egg travels from the ovary through a Fallopian tube to the uterus.
Unless pregnancy occurs, the cycle ends with the shedding of part of the inner lining of the uterus, which results in menstruation. Although it is actually the end of the physical cycle, the first day of menstrual bleeding is designated as "day 1" of the menstrual cycle in medical jargon.
The time of the cycle during which menstruation occurs is referred to as menses. The menses occurs at approximately four-week intervals, representing the menstrual cycle.
Menarche is the time in a girl's life when menstruation first begins. Menopause is the time in a woman's life when the function of the ovaries ceases and menstrual periods stop. Menopause is defined as the absence of menstrual periods for 12 consecutive months. The average age of menopause is 51 years old.
What is abnormal vaginal bleeding?
Abnormal vaginal bleeding is a flow of blood from the vagina that occurs either at the wrong time during the month or in inappropriate amounts. In order to determine whether bleeding is abnormal, and its cause, the doctor must consider three questions:
- Is the woman pregnant?
- What is the pattern of the bleeding?
- Is she ovulating?
Every woman who thinks she has an irregular menstrual bleeding pattern should think carefully about the specific characteristics of her vaginal bleeding in order to help her doctor evaluate her particular situation. Her doctor will require the details of her menstrual history. Each category of menstrual disturbance has a particular list of causes, necessary testing, and treatment. Each type of abnormality is discussed individually below.
1. Is the woman having abnormal vaginal bleeding during pregnancy?
Much of the abnormal vaginal bleeding during pregnancy occurs so early in the pregnancy that the woman doesn't realize she is pregnant. Therefore, irregular bleeding that is new may be a sign of very early pregnancy, even before a woman is aware of her condition. Vaginal bleeding during pregnancy can also be associated with complications of pregnancy, such as miscarriage or ectopic pregnancy.
2. What is the pattern of the abnormal vaginal bleeding?
The duration, interval, and amount of vaginal bleeding may suggest what type of abnormality is responsible for the bleeding.
An abnormal duration of menstrual bleeding can be either bleeding for too long of a period (hypermenorrhea), or too short of a period (hypomenorrhea).
The interval of the bleeding can be abnormal in several ways. A woman's menstrual periods can occur too frequently (polymenorrhea) or too seldom (oligomenorrhea). Additionally, the duration can vary excessively from cycle to cycle (metrorrhagia).
The amount (volume) of bleeding can also be abnormal. A woman can either have too much bleeding (menorrhagia) or too little volume (hypomenorrhea). The combination of excessive bleeding combined with bleeding outside of the expected time of menstruation is referred to as menometrorrhagia.
3. Is the woman ovulating?
Usually, the ovary releases an egg every month in a process called ovulation. Normal ovulation is necessary for regular menstrual periods. There are certain clues that a woman is ovulating normally including regular menstrual intervals, vaginal mucus discharge halfway between menstrual cycles, and monthly symptoms including breast tenderness, fluid retention, menstrual cramps, back pain, and mood changes. If necessary, doctors will order hormone blood tests (progesterone level), daily home body temperature testing, or rarely, a sampling of the lining of the uterus (endometrial biopsy) to determine whether or not a woman is ovulating normally.
On the other hand, signs that a woman is not ovulating regularly include prolonged bleeding at irregular intervals after not having a menstrual period for several months, excessively low blood progesterone levels in the second half of the menstrual cycle, and lack of the normal body temperature fluctuation during the time of expected ovulation. Sometimes, a doctor determines that a woman is not ovulating by using endometrial sampling with biopsy.
What conditions cause abnormal vaginal bleeding in women who are ovulating regularly?
Abnormal vaginal bleeding in women who are ovulating regularly, most commonly involve excessive, frequent, irregular, or decreased bleeding. Some of the common conditions that produce each of these symptoms are discussed below.
Excessively heavy menstrual bleeding (menorrhagia)
Excessively heavy menstrual bleeding, called menorrhagia, is menstrual bleeding of greater than about eight tablespoons per month (normal menstrual bleeding produces between two and eight tablespoons per cycle). The most common pattern of menorrhagia is excessive bleeding that occurs in regular menstrual cycles and with normal ovulation.
There are several important reasons that menorrhagia should be evaluated by a doctor. First, menorrhagia can cause a woman substantial emotional distress and physical symptoms, such as severe cramping. Second, the blood loss can be so severe that it causes a dangerously lowered blood count (anemia), which can lead to medical complications and symptoms such as dizziness and fainting. Third, there can be dangerous causes of menorrhagia that require more urgent treatment.
Benign (noncancerous) causes of menorrhagia include:
- Uterine fibroids (benign tumors of smooth muscle; this type of tumor is known as a leiomyoma)
- Endometrial polyps (tiny benign growths that protrude into the womb)
- Adenomyosis (the presence of uterine lining tissue within the muscular wall of the uterus)
- Intrauterine devices (IUD's)
- Underactive thyroid function (hypothyroidism)
- The autoimmune disorder systemic lupus erythematosus
- Blood clotting disorders such as inherited bleeding disorders
- Certain medications, especially those that interfere with blood clotting
Though not common, menorrhagia can be a sign of endometrial cancer. A potentially precancerous condition known as endometrial hyperplasia can also result in abnormal vaginal bleeding. This situation is more frequent in women who are over the age of 40.
Although there are many causes of menorrhagia, in most women, the specific cause of menorrhagia is not found even after a full medical evaluation. These women are said to have dysfunctional uterine bleeding. Although no specific cause of the abnormal vaginal bleeding is found in women with dysfunctional uterine bleeding, there are treatments available to reduce the severity of the condition.
Irregular vaginal bleeding; menstrual periods that are too frequent (polymenorrhea)
Menstrual periods that are abnormally frequent (polymenorrhea) can be caused by certain sexually transmitted diseases (STDs) (such as Chlamydia or gonorrhea) that cause inflammation in the uterus. This condition is called pelvic inflammatory disease. Endometriosis is a condition of unknown cause that results in the presence of uterine lining tissue in other locations outside of the uterus. This can lead to pelvic pain and polymenorrhea. Sometimes, the cause of polymenorrhea is unclear, in which case the woman is said to have dysfunctional uterine bleeding.
Menstrual periods at irregular intervals (metrorrhagia)
Irregular menstrual periods (metrorrhagia) can be due to benign growths in the cervix, such as cervical polyps. The cause of these growths is usually not known. Metrorrhagia can also be caused by infections of the uterus (endometritis) and use of birth control pills (oral contraceptives). Sometimes after an evaluation, a woman's doctor might determine that her metrorrhagia does not have an identifiable cause and that further evaluation is not necessary at that time.
Perimenopause is the time period approaching or around menopause. It often is characterized by irregular menstrual cycles, including menstrual periods at irregular intervals and variations in the amount of blood flow. Menstrual irregularities may precede the onset of true menopause (defined as the absence of periods for one year) by several years.
Decreased amount or duration of menstrual flow (hypomenorrhea)
An overactive thyroid function (hyperthyroidism) or certain kidney diseases can both cause hypomenorrhea. Oral contraceptive pills can also cause hypomenorrhea. It is important for women to know that lighter, shorter, or even absent menstrual periods as a result of taking oral contraceptive pills does not indicate that the contraceptive effect of the oral contraceptive pills is inadequate. In fact, many women appreciate this "side effect" of oral contraceptives.
Bleeding between menstrual periods (intermenstrual bleeding)
Women who are ovulating normally can experience light bleeding (sometimes referred to as "spotting") between menstrual periods. Hormonal birth control methods (oral contraceptive pills or patches) as well as IUD use for contraception may sometimes lead to light bleeding between periods. Psychological stress, certain medications such as anticoagulant drugs, and fluctuations in hormone levels may all be causes of light bleeding between periods. Other conditions that cause abnormal menstrual bleeding, or bleeding in women who are not ovulating regularly also can be the cause of intermenstrual bleeding.
What conditions cause vaginal bleeding after menopause or abnormal vaginal bleeding in women who are not ovulating regularly?
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, PCOS, 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.
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).
What causes abnormal vaginal bleeding during pregnancy?
Many women have some amount of vaginal bleeding during pregnancy. Some studies show that up to 20% to 30% of pregnant women will experience some degree of vaginal bleeding while they are pregnant. Vaginal bleeding during pregnancy is more common with twins and other multiple gestations than with singleton pregnancies (pregnancy with one fetus).
Sometimes women experience a very scant amount of bleeding in the first two weeks of pregnancy, usually around the time of the expected menstrual period. This slight bleeding is sometimes referred to as "implantation bleeding." Doctors do not know for certain what causes this bleeding, but it may occur as a result of the fertilized egg implanting in the uterine wall.
The amount of the bleeding, the stage of pregnancy, and any associated symptoms can all help determine the cause of vaginal bleeding in pregnancy. While vaginal bleeding in pregnancy does not always signify a problem with the pregnancy, women who experience bleeding during pregnancy should be evaluated by a doctor.
Causes of vaginal bleeding in pregnancy include miscarriage, an abnormal location of the placenta, ectopic pregnancy, cervical infection or polyp, and premature labor. Chronic medical conditions and medication use can also be related to vaginal bleeding during pregnancy.
What causes vaginal bleeding during or after sexual intercourse?
Vaginal bleeding may occur during or after sexual intercourse for a number of reasons including:
- Injuries to the vaginal wall or introitus (opening to the vagina) during intercourse
- Infections (for example, gonorrhea, Chlamydia, yeast infections) can be a cause of vaginal bleeding after intercourse.
- Lowered estrogen levels in peri-menopausal or postmenopausal women may cause the lining of the vagina to become thinned and easily inflamed or infected, and these changes can be associated with vaginal bleeding after intercourse.
- Anatomical lesions, such as tumors or polyps on the cervix or vaginal wall may lead to vaginal bleeding during or after intercourse.
Women who experience vaginal bleeding during or following sexual intercourse should always visit their doctor to determine the cause of the bleeding.
What diagnostic tests are used to evaluate abnormal vaginal bleeding?
- A woman who has irregular menstrual periods requires a physical examination with a special emphasis on the thyroid, breast, and pelvic area. During the pelvic examination, the physician attempts to detect cervical polyps or any unusual masses in the uterus or ovaries.
- A Pap smear is also done to rule out cervical cancer. While the Pap smear is being obtained, samples might be taken from the cervix to test for the presence of infections such as chlamydia or gonorrhea.
- A pregnancy test is routine if the woman is premenopausal.
- A blood count may be done to rule out a low blood count (anemia) resulting from excessive blood loss.
- If something in the patient's (or her family's) medical background or physical examination raises a doctor's suspicion, tests to rule out certain blood clotting disorders may be done.
- Sometimes, a blood sample will be tested to evaluate thyroid function, liver function, or kidney function abnormalities.
- A blood test for progesterone levels or daily body temperature charting may be recommended to verify that the woman ovulates.
- If the doctor suspects that the ovaries are failing, such as with menopause, blood levels of follicle-stimulating hormone (FSH) may be tested.
- Additional blood hormone tests are done if the doctor suspects polycystic ovary, or if excessive hair growth is present.
- A pelvic ultrasound is often performed based on the woman's medical history and pelvic examination.
- If a woman does not adequately respond to medical treatment, if she is over age 40, or if she has persistent vaginal bleeding between her periods, a sampling of the lining of her uterus (termed endometrial sampling or endometrial biopsy) is often analyzed. Endometrial sampling helps to rule out cancer or precancer in the uterus, or it can confirm a suspicion that a woman is not ovulating.
How is irregular vaginal bleeding treated?
Treatment for irregular vaginal bleeding depends on the underlying cause. After the cause is determined, the doctor decides if treatment is actually necessary. Sometimes, all that is needed is for dangerous causes to be ruled out and to determine that the irregular vaginal bleeding does not bother the woman enough to warrant medication or treatment. If thyroid, liver, kidney, or blood clotting problems are discovered, treatment is directed toward these conditions.
Medications for treatment of irregular vaginal bleeding depend on the cause. Examples are described below:
- If the cause of the bleeding is lack of ovulation (anovulation), doctors may prescribe either progesterone to be taken at regular intervals, or an oral contraceptive, which contains progesterone, to achieve a proper hormonal balance. Such treatment dramatically decreases the risk of uterine cancer in women who do not ovulate.
- If the cause of irregular vaginal bleeding is a precancerous change in the lining of the uterus, progesterone medications may be prescribed to reduce the buildup of precancerous uterine lining tissues in an attempt to avoid surgery.
- When a woman has been without menses for less than six months and is bleeding irregularly, the cause may be that she is approaching menopause. During this transition, a woman is sometimes offered an oral contraceptive to establish a more regular bleeding pattern, to provide contraception until she achieves menopause (defined as 12 months without a menstrual period), and to relieve hot flashes. A woman who is found to be menopausal as the cause of her irregular bleeding may also receive menopause counseling if she has troubling symptoms.
- If the cause of irregular vaginal bleeding is polyps or other benign growths, these are sometimes removed surgically to control bleeding because they cannot be treated with medication.
- If the cause of bleeding is infection, antibiotics are necessary. Bleeding during pregnancy requires prompt evaluation by an obstetrician. Endometriosis can be treated with medications and/or surgery (such as laparoscopy).
- Sometimes, the cause of excessive bleeding is not apparent after completion of testing (dysfunctional uterine bleeding). In these cases, oral contraceptives can improve cycle control and lessen bleeding.
- If bleeding is excessive and cannot be controlled by medication, a surgical procedure called dilation and curettage (D&C) may be necessary. In addition to alleviating the excessive bleeding, the D&C provides tissue that can be analyzed for additional information that can rule out abnormalities of the lining of the uterus.
- Occasionally, a hysterectomy is necessary when hormonal medications cannot control excessive bleeding. However, unless the cause is pre-cancerous or cancerous, this surgery should only be an option after other solutions have been tried.
Many new procedures are being developed to treat certain types of irregular vaginal bleeding. For example, studies are underway to evaluate techniques that selectively block the blood vessels involved in the bleeding. These newer methods may be less complicated options for some patients and as they are further evaluated they will likely become more widely available.
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Medically reviewed by Wayne Blocker, MD; American Board of Obstetrics & Gynecology.
Behera, M.A., MD. "Abnormal (Dysfunctional) Uterine Bleeding." Medscape. Updated Nov 15, 2015.
Giuntoli, II, R. et al. "Classification and diagnosis of endometrial hyperplasia." UpToDate. Updated Nov 24, 2014.