Amenorrhea (uh-men-o-REE-uh) is the absence of menstruation — one or more missed menstrual periods. Women who have missed at least three menstrual periods in a row have amenorrhea, as do girls who haven't begun menstruation by age 15.
The most common cause of amenorrhea is pregnancy. Other causes of amenorrhea include problems with the reproductive organs or with the glands that help regulate hormone levels. Treatment of the underlying condition often resolves amenorrhea.
The main sign of amenorrhea is the absence of menstrual periods. Depending on the cause of amenorrhea, you might experience other signs or symptoms along with the absence of periods, such as:
Consult your doctor if you've missed at least three menstrual periods in a row, or if you've never had a menstrual period and you're age 15 or older.
Amenorrhea can occur for a variety of reasons. Some are normal during the course of a woman's life, while others may be a side effect of medication or a sign of a medical problem.
During the normal course of your life, you may experience amenorrhea for natural reasons, such as:
Some women who take birth control pills may not have periods. Even after stopping oral contraceptives, it may take some time before regular ovulation and menstruation return. Contraceptives that are injected or implanted also may cause amenorrhea, as can some types of intrauterine devices.
Certain medications can cause menstrual periods to stop, including some types of:
Sometimes lifestyle factors contribute to amenorrhea, for instance:
Many types of medical problems can cause hormonal imbalance, including:
Problems with the sexual organs themselves also can cause amenorrhea. Examples include:
Ovulation is the release of an egg from one of the ovaries. It often happens about midway through the menstrual cycle, although the exact timing may vary.
In preparation for ovulation, the lining of the uterus, or endometrium, thickens.
The pituitary gland in the brain stimulates one of the ovaries to release an egg.
The wall of the ovarian follicle ruptures at the surface of the ovary. The egg is released.
Finger-like structures called fimbriae sweep the egg into the neighboring fallopian tube.
The egg travels through the fallopian tube, propelled in part by contractions in the fallopian tube walls.
Here in the fallopian tube, the egg may be fertilized by a sperm.
If the egg is fertilized, the egg and sperm unite to form a one-celled entity called a zygote.
As the zygote travels down the fallopian tube toward the uterus, it begins dividing rapidly to form a cluster of cells resembling a tiny raspberry.
When the zygote reaches the uterus, it implants in the lining of the uterus and pregnancy begins.
If the egg isn't fertilized, it's simply reabsorbed by the body — perhaps before it even reaches the uterus. About two weeks later, the lining of the uterus sheds through the vagina. This is known as menstruation.
During your appointment, your doctor will perform a pelvic exam to check for any problems with your reproductive organs. If you've never had a period, your doctor may examine your breasts and genitals to see if you're experiencing the normal changes of puberty.
Amenorrhea can be a sign of a complex set of hormonal problems. Finding the underlying cause can take time and may require more than one kind of testing.
A variety of blood tests may be necessary, including:
For this test, you take a hormonal medication for seven to 10 days to trigger menstrual bleeding. Results from this test can tell your doctor whether your periods have stopped due to a lack of estrogen.
Depending on your signs and symptoms — and the result of any blood tests you've had — your doctor might recommend one or more imaging tests, including:
If other testing reveals no specific cause, your doctor may recommend a hysteroscopy — a test in which a thin, lighted camera is passed through your vagina and cervix to look at the inside of your uterus.
Complications of amenorrhea may include:
Some lifestyle factors — such as too much exercise or too little food — can cause amenorrhea, so strive for balance in work, recreation and rest. Assess areas of stress and conflict in your life. If you can't decrease stress on your own, ask for help from family, friends or your doctor.
Be aware of changes in your menstrual cycle and check with your doctor if you have concerns. Keep a record of when your periods occur. Note the date your period starts, how long it lasts and any troublesome symptoms you experience.
Factors that may increase your risk of amenorrhea may include: