Premature ovarian failure — also known as primary ovarian insufficiency — is a loss of normal function of your ovaries before age 40. If your ovaries fail, they don't produce normal amounts of the hormone estrogen or release eggs regularly. Infertility is a common result.
Premature ovarian failure is sometimes referred to as premature menopause, but the two conditions aren't the same. Women with premature ovarian failure can have irregular or occasional periods for years and might even become pregnant. Women with premature menopause stop having periods and can't become pregnant.
Restoring estrogen levels in women with premature ovarian failure helps prevent some complications, such as osteoporosis, that occur as a result of low estrogen.
Signs and symptoms of premature ovarian failure are similar to those of going through menopause and are typical of estrogen deficiency. They include:
- Irregular or skipped periods (amenorrhea), which might be present for years or develop after a pregnancy or after stopping birth control pills
- Difficulty conceiving
- Hot flashes
- Night sweats
- Vaginal dryness
- Irritability or difficulty concentrating
- Decreased sexual desire
When to see a doctor
If you've missed your period for three months or more, see your doctor to help determine the cause. You can miss your period for a number of reasons — including pregnancy, stress, or a change in diet or exercise habits — but it's best to get evaluated whenever your menstrual cycle changes.
Even if you don't mind not having periods, it's advisable to see your doctor to find out what's causing the change. Low estrogen levels can lead to bone loss.
In women with normal ovarian function, the pituitary gland releases certain hormones during the menstrual cycle, which causes a small number of egg-containing follicles in the ovaries to begin maturing. Usually one or two follicles — tiny sacs filled with fluid — reach maturity each month.
When the follicle matures, it opens, releasing an egg. The egg enters the fallopian tube where a sperm cell might fertilize it, resulting in pregnancy.
Premature ovarian failure results from the loss of eggs (oocytes). This might happen because of:
- Chromosomal defects. Certain genetic disorders are associated with premature ovarian failure. These include mosaic Turner's syndrome — in which a woman has only one normal X chromosome and an altered second X chromosome — and fragile X syndrome — in which the X chromosomes are fragile and break.
- Toxins. Chemotherapy and radiation therapy are the most common causes of toxin-induced ovarian failure. These therapies can damage the genetic material in cells. Other toxins such as cigarette smoke, chemicals, pesticides and viruses might hasten ovarian failure.
- An immune system response to ovarian tissue (autoimmune disease). In this rare form, your immune system produces antibodies against your ovarian tissue, harming the egg-containing follicles and damaging the egg. What triggers the immune response is unclear, but exposure to a virus is one possibility.
- Unknown factors. It's possible to develop premature ovarian failure, but have no known chromosomal defects, toxin exposure or autoimmune disease. Your doctor might recommend further testing to find the cause, but in most cases, the cause remains unknown (idiopathic).
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 called a blastocyst, which resembles a tiny raspberry. When the blastocyst 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.
Factors that increase your risk of developing premature ovarian failure include:
- Age. Risk rises between the ages of 35 and 40, although younger women and adolescents can develop the condition.
- Family history. Having a family history of premature ovarian failure increases your risk of developing this disorder.
- Multiple ovarian surgeries. Ovarian endometriosis or other conditions requiring repeated surgeries on the ovaries increases the risk of premature ovarian failure.
Complications of premature ovarian failure include:
- Infertility. Inability to get pregnant may be the most troubling complication of premature ovarian failure, although in rare cases, pregnancy is possible until the eggs are depleted.
- Osteoporosis. The hormone estrogen helps maintain strong bones. Women with low levels of estrogen have an increased risk of developing weak and brittle bones (osteoporosis), which are more likely to break than healthy bones.
- Depression or anxiety. The risk of infertility and other complications arising from low estrogen levels causes some women to become depressed or anxious.
- Heart disease. Early loss of estrogen might increase your risk.
- Dementia. Lack of estrogen can contribute to this in some people.