Abnormal uterine bleeding in women in the reproductive years is bleeding from the uterus that does not follow the normal pattern for menstrual cycles. That is, it occurs too frequently or is irregular or lasts longer or is heavier than normal menstrual periods.
The most common type of abnormal bleeding results from problems that interfere with the release of the egg (ovulation).
To evaluate abnormal uterine bleeding, doctors ask women questions about the pattern of bleeding (menstrual history), and do a physical exam (including a pelvic examination) and sometimes other tests such as ultrasound, blood tests, or a biopsy of the lining of the uterus.
A biopsy of the lining of the uterus may be done.
Treatment depends on the cause and may include hormones or other medications, such as a combination birth control pill, or a procedure, such as hysteroscopy and dilation and curettage (D and C)
If the biopsy detects abnormal cells, treatment involves high doses of a progestin and sometimes removal of the uterus.
(See also Vaginal Bleeding.)
Abnormal uterine bleeding is a common problem in women during their reproductive years. It occurs most commonly at the beginning and end of the reproductive years (in adolescent girls and women aged 45 years and over).
For women in the reproductive years, the most common cause of abnormal bleeding is ovulatory dysfunction. That is, the ovaries do not release an egg (ovulate) or do not regularly release an egg. Thus, pregnancy is less likely. However, because the ovaries may occasionally release an egg, women with ovulatory dysfunction should use contraception if they do not wish to become pregnant. Often, what causes the ovaries to malfunction is not known.
Abnormal uterine bleeding commonly results when the level of estrogen remains high instead of decreasing as it normally does after an egg is released and is not fertilized. The high estrogen level is not balanced by an appropriate level of progesterone. In women with this type of abnormal bleeding, no egg is released, and the lining of the uterus (endometrium) may continue to thicken (instead of breaking down and being shed normally as a menstrual period). This abnormal thickening is called endometrial hyperplasia. Periodically, the thickened lining is shed incompletely and irregularly, causing bleeding. Bleeding is irregular, prolonged, and sometimes heavy and may last many days. This type of abnormal uterine bleeding is called anovulatory uterine bleeding.
In other women, an egg is released but progesterone production lasts longer than usual. As a result, the thickened lining of the uterus is shed irregularly. This type of abnormal uterine bleeding pattern is called ovulatory dysfunction (a woman does not ovulate or ovulation does not occur every month). In women with obesity, this type can occur when estrogen levels are high. As a result, intervals with no periods alternate with intervals of prolonged bleeding.
If this cycle of abnormal thickening and irregular shedding continues, precancerous cells may develop, increasing the risk of cancer of the uterine lining (endometrial cancer), even in young women.
Abnormal uterine bleeding is often an early sign of perimenopause (the several years before and up to 1 year after the last menstrual period).
Causes of Abnormal Uterine Bleeding
Doctors classify causes of abnormal bleeding as due to an abnormality in a a part of the body (structural) or due to another problem (nonstructural).
Structural causes include:
Adenomyosis (when endometrial tissue grows into the wall of the uterus)
Precancerous conditions (hyperplasia—when the uterine lining is thickened but its cells are normal)
Cancer
Nonstructural causes include:
Ovulatory dysfunction
Use of contraceptives or certain medications
Abnormal uterine bleeding due to ovulatory dysfunction (AUB-O) is the most common cause of nonstructural abnormal bleeding and the most common cause overall. Causes of ovulatory dysfunction include:
Premature menopause (primary ovarian insufficiency)
Changes that occur around puberty or during the years before menopause occurs and the 1 year after (perimenopause)
Bodywide disorders, such as liver disease or kidney disease
Extreme physical or emotional stress
Poor nutrition
Sometimes the cause is unknown.
Symptoms of Abnormal Uterine Bleeding
Compared with typical menstrual periods, abnormal uterine bleeding, may have the following characteristics:
Increased frequency (first day of each period occurs fewer than 24 days apart)
Irregular (number of days vary from first day of one period to the next period)
Prolonged bleeding (lasts longer than 8 days)
Heavy bleeding (loss of more than about 3 ounces of blood)
Intermenstrual bleeding (occurs between periods)
Symptoms depend on the cause of bleeding. Bleeding may be abnormal during regular menstrual cycles, or bleeding may occur at unpredictable times. Some women have symptoms associated with menstrual periods, such as breast tenderness, cramping, and bloating, but many do not.
If bleeding continues, women may develop iron deficiency and sometimes anemia.
Whether infertility develops depends on the cause of the bleeding.
Diagnosis of Abnormal Uterine Bleeding
Description of the pattern of bleeding currently and before the menstrual cycle problem started
Pregnancy test
A complete blood count
Measurement of hormone levels
Pelvic imaging studies, usually pelvic ultrasound
Sometimes procedures such as an endometrial biopsy or hysteroscopy
Abnormal uterine bleeding is suspected when bleeding occurs at irregular times or in excessive amounts.
To establish that bleeding is abnormal, clinicians ask questions about the pattern of bleeding (menstrual history).
To determine the cause, clinicians ask about other symptoms and possible causes (such as use of medications, the presence of other disorders, fibroids, and complications during pregnancies).
A physical examination is also done.
Tests to check for possible causes of abnormal uterine bleeding
Doctors do a pregnancy test, even in adolescent girls and women who are going through menopause.
Other tests to check for possible causes of vaginal bleeding may be done based on the findings during the interview and physical examination. For example, clinicians usually do a complete blood count to estimate how much blood has been lost and whether anemia (including iron deficiency anemia) is present. They also may do blood tests to determine how fast blood clots (to check for clotting disorders).
Doctors typically do blood tests to measure hormone levels (to check for polycystic ovary syndrome, thyroid disorders, pituitary disorders, or other disorders that are common causes of vaginal bleeding). Hormones that may be measured include female hormones such as estrogen or progesterone (which helps control the menstrual cycle), thyroid hormones, pituitary hormones, and prolactin.
Doctors may do a cervical cancer screening test, such as a Papanicolaou (Pap) test and/or human papillomavirus (HPV) test, if women have not been tested recently.
Doctors may also do an imaging test or a procedure. For example, they may do a biopsy if results of blood tests or a Pap test are abnormal or do not identify the cause of the bleeding.
Imaging tests and procedures
Pelvic ultrasound (done with a handheld device that is passed over the lower abdomen and then usually also using a small handheld device inserted through the vagina to view the reproductive system internal organs [cervix, uterus, tubes, and ovaries]) is usually used to check for growths in the uterus and to determine whether the uterine lining (endometrium) is thickened. Thickening of the uterine lining may result from noncancerous conditions such as polyps or fibroids or hormonal changes. (The hormonal changes that cause abnormal uterine bleeding can result in such thickening, and may cause precancerous cells to develop and increase the risk of endometrial cancer.)
Pelvic ultrasound is done if women have any of the following (which includes most women with abnormal uterine bleeding):
Risk factors for endometrial cancer, such as obesity, diabetes, high blood pressure, polycystic ovary syndrome, and excess body hair (hirsutism), regardless of age
Women 45 years old or over who are not in menopause
Postmenopausal women
Bleeding that continues despite treatment with hormones
Pelvic or reproductive organs that cannot be examined adequately during the physical examination
Abnormalities of the uterus or ovaries are suspected based on bleeding pattern, other symptoms, or pelvic examination
Pelvic ultrasound can detect structural abnormalities, including endometrial thickening (thickening in the lining of the uterus), endometrial polyps, fibroids, other uterine masses, adenomyosis (growth of endometrial tissue into the wall of the uterus), and ovarian or fallopian tube abnormalities. One or both of the following tests may be done:
Sonohysterography (ultrasound after saline is infused into the uterus)
Hysteroscopy (insertion of a viewing tube through the vagina to view the uterus)
An endometrial biopsy is usually also done to check for precancerous changes and for cancer in women with any of the following:
Women 45 years old or over who are not in menopause
Age under 45 years with one or more risk factors for endometrial cancer
Bleeding that is persistent or recurs despite treatment
Postmenopausal women with risk factors for uterine cancer or abnormal pelvic ultrasound (thickening of the uterine lining)
Inconclusive findings during pelvic ultrasound
Treatment of Abnormal Uterine Bleeding
Medications to control the bleeding
Sometimes progestin therapy for endometrial hyperplasia
If bleeding continues, a procedure to control the bleeding
Hysterectomy (removal of the uterus) for persistent bleeding (depending on a woman's preference and other treatment options) or for endometrial hyperplasia (uterine lining is thickened but cells are normal) or cancer
If iron deficiency anemia is present, iron supplements
Treatment of abnormal uterine bleeding depends on the following:
How old the woman is
How heavy the bleeding is
Whether the uterine lining is thickened
Whether the woman wishes to become pregnant
Treatment focuses on controlling the bleeding and, if needed, preventing endometrial cancer.
Medications
Bleeding can be controlled using medications, which may be hormones or not.
Medications that are not hormones are often used first, especially in women who want to become pregnant or to avoid the side effects of hormone therapy and in women with heavy regular bleeding. These medications include:
Nonsteroidal anti-inflammatory drugs (NSAIDs)
Tranexamic acidTranexamic acid
Hormone therapy (such as birth control pills) is often tried first in women who do not want to become pregnant or who are approaching or just past menopause (this time period is called perimenopause).
When the uterine lining is thickened but its cells are normal (endometrial hyperplasia), hormones may be used to control bleeding.
Often, a birth control pill that contains estrogen and a progestin (a combination oral contraceptive) is used. Besides controlling bleeding, oral contraceptives decrease the cramping that may accompany bleeding. They also decrease the risk of endometrial (and ovarian) cancer. Bleeding usually stops in 12 to 24 hours. Sometimes high doses are needed to control the bleeding. After bleeding stops, low doses of the oral contraceptive may then be prescribed for at least 3 months to prevent the bleeding from recurring.
Some women should not take estrogen, including that in combination oral contraceptives, including:
Women with significant risk factors for a heart or blood vessel disorder or who have had blood clots
Women who have had a baby within the last month
A progestin or progesteroneprogestin or progesterone (which is similar to the hormone the body makes) may be used alone when:
Women should not take estrogen (that is, when estrogen is contraindicated).
Treatment with estrogen is ineffective or not tolerated.
Women do not wish to take estrogen.
Progestins and progesterone can be given by mouth for 21 days a month. When these hormones are taken this way, they may not prevent pregnancy. Thus, if women do not wish to become pregnant, they must use another method of birth control, such as a progestin-only contraceptive, Progestins and progesterone can be given by mouth for 21 days a month. When these hormones are taken this way, they may not prevent pregnancy. Thus, if women do not wish to become pregnant, they must use another method of birth control, such as a progestin-only contraceptive,intrauterine device (IUD) or medroxyprogesterone given by injection every few months.
Other medications that are occasionally used to treat abnormal uterine bleeding include danazol (a synthetic male hormone, or androgen) and gonadotropin-releasing hormone (GnRH) agonists (synthetic forms of a hormone produced by the body, sometimes used to treat bleeding caused by fibroids and temporarily shrink fibroids). However, these medications have significant side effects that limit their use to a few months. Danazol is not frequently used because it has many side effects.(synthetic forms of a hormone produced by the body, sometimes used to treat bleeding caused by fibroids and temporarily shrink fibroids). However, these medications have significant side effects that limit their use to a few months. Danazol is not frequently used because it has many side effects.
If heavy menstrual bleeding is thought to be caused by fibroids, other oral medications, some of which contain hormones, may be used (see also Fibroid Treatment).
If women are trying to become pregnant and bleeding is not too heavy, they may be given clomiphene (a fertility drug) by mouth instead of hormones. It stimulates ovulation.If women are trying to become pregnant and bleeding is not too heavy, they may be given clomiphene (a fertility drug) by mouth instead of hormones. It stimulates ovulation.
If women have iron deficiency anemia or symptoms of iron deficiency without anemia, iron supplements are usually given by mouth but sometimes must be given by vein (intravenously). Normal consumption of iron in the diet usually cannot compensate for iron loss due to chronic bleeding, and the body has a very small iron reserve. Consequently, lost iron must be replaced by taking iron supplements.
Procedures
If the uterine lining (endometrium) remains thickened or the bleeding persists despite treatment with hormones, hysteroscopy is usually done in an operating room or outpatient procedure room to look into the uterus. It is followed by dilation and curettage (D and C) and removal of any masses seen on hysteroscopy. For a D and C, tissue from the uterine lining is removed by scraping. This procedure may reduce bleeding for a few months. However, in some women, it causes scarring of the endometrium (Asherman syndrome). Scarring can cause menstrual bleeding to stop (amenorrhea) and make biopsy of the endometrium difficult later.
If bleeding continues after a D and C, a procedure that destroys or removes the lining of the uterus (endometrial ablation) can often help control bleeding. This procedure may use burning, freezing, or other techniques and decreases bleeding in most women. Endometrial ablation causes scarring of the endometrium and decreased bleeding but does not prevent pregnancy.
If fibroids are the cause, blood flow to the fibroids may be blocked with small, synthetic particles injected through a thin, flexible tube (catheter) into these arteries (called artery embolization or uterine fibroid embolization). Alternatively, fibroids may be removed through a catheter inserted into a small incision just below the navel (laparoscopy), through a catheter inserted into the vagina (hysteroscopy), or through a larger incision into the abdomen. Radiofrequency fibroid ablation can be used during hysteroscopy or laparoscopy to destroy, rather than remove, fibroids. Alternatively, magnetic resonance-guided focused ultrasound surgery uses sound waves to destroy fibroids.
If bleeding continues to be substantial after other treatments have been tried, doctors may recommend removal of the uterus (hysterectomy).
Management of acute uterine bleeding
Rarely, very heavy bleeding requires emergency measures. They may include fluids given intravenously and blood transfusions.
Occasionally, doctors insert a catheter with a deflated balloon at its tip through the vagina and into the uterus. The balloon is inflated to put pressure on the bleeding vessels and thus stop the bleeding.
Very rarely, estrogen is given intravenously. Treatment is limited to 4 doses because this treatment increases the risk of blood clots. Immediately afterward, women are given combination oral contraceptives until bleeding has been controlled for a few months.
If bleeding cannot be controlled with conservative measures, hysterectomy is an option. However, all attempts are made to avoid this, particularly in women with plans for future childbearing.
Drugs Mentioned In This Article
