Primary ovarian insufficiency (POI), also known as premature ovarian failure, happens when a woman's ovaries stop working normally before she is 40.

Many women naturally experience reduced fertility when they are about 40 years old. They may start getting irregular menstrual periods as they transition to menopause. For women with POI, irregular periods and reduced fertility start before the age of 40. Sometimes it can start as early as the teenage years.

POI is different from premature menopause. With premature menopause, your periods stop before age 40. You can no longer get pregnant. The cause can be natural or it can be a disease, surgery, chemotherapy, or radiation. With POI, some women still have occasional periods. They may even get pregnant. In most cases of POI, the cause is unknown.

In about 90% of cases, the exact cause of POI is unknown.

Research shows that POI is related to problems with the follicles. Follicles are small sacs in your ovaries. Your eggs grow and mature inside them. One type of follicle problem is that you run out of working follicles earlier than normal. Another is that the follicles are not working properly. In most cases, the cause of the follicle problem is unknown. But sometimes the cause may be:

• Genetic disorders such as Fragile X syndrome and Turner syndrome
• A low number of follicles
• Autoimmune diseases, including thyroiditis and Addison disease
• Chemotherapy or radiation therapy
• Metabolic disorders
• Toxins, such as cigarette smoke, chemicals, and pesticides

Certain factors can raise a woman's risk of POI:

• Family history. Women who have a mother or sister with POI are more likely to have it.
• Genes. Some changes to genes and genetic conditions put women at higher risk for POI. For example, women Fragile X syndrome or Turner syndrome are at higher risk.
• Certain diseases, such as autoimmune diseases and viral infections
• Cancer treatments, such as chemotherapy and radiation therapy
• Age. Younger women can get POI, but it becomes more common between the ages of 35-40.

The first sign of POI is usually irregular or missed periods. Later symptoms may be similar to those of natural menopause:

• Hot flashes
• Night sweats
• Irritability
• Poor concentration
• Decreased sex drive
• Pain during sex
• Vaginal dryness

For many women with POI, trouble getting pregnant or infertility is the reason they go to their health care provider.

Since POI causes you to have lower levels of certain hormones, you are at greater risk for other health conditions, including:

• Anxiety and depression. Hormonal changes caused by POI can contribute to anxiety or lead to depression.
• Dry eye syndrome and eye surface disease. Some women with POI have one of these eye conditions. Both can cause discomfort and may lead to blurred vision. If not treated, these conditions can cause permanent eye damage.
• Heart disease. Lower levels of estrogen can affect the muscles lining the arteries and can increase the buildup of cholesterol in the arteries. These factors increase your risk of atherosclerosis (hardening of the arteries).
• Infertility.
• Low thyroid function. This problem also is called hypothyroidism. The thyroid is a gland that makes hormones that control your body's metabolism and energy level. Low levels of thyroid hormones can affect your metabolism and can cause very low energy, mental sluggishness, and other symptoms.
• Osteoporosis. The hormone estrogen helps keep bones strong. Without enough estrogen, women with POI often develop osteoporosis. It is a bone disease that causes weak, brittle bones that are more likely to break.

To diagnose POI, your health care provider may do:

• A medical history, including asking whether you have relatives with POI
• A pregnancy test, to make sure that you are not pregnant
• A physical exam, to look for signs of other disorders that could be causing your symptoms
• Blood tests, to check for certain hormone levels. You may also have a blood test to do a chromosome analysis. A chromosome is the part of a cell that contains genetic information.
• A pelvic ultrasound, to see whether or not the ovaries are enlarged or have multiple follicles

Currently, there is no proven treatment to restore normal function to a woman's ovaries. But there are treatments for some of the symptoms of POI. There are also ways to lower your health risks and treat the conditions that POI can cause:

• Hormone replacement therapy (HRT).HRT is the most common treatment. It gives your body the estrogen and other hormones that your ovaries are not making. HRT improves sexual health and decreases the risks for heart disease and osteoporosis. You usually take it until about age 50; that's about the age when menopause usually begins.
• Calcium and vitamin D supplements. Because women with POI are at higher risk for osteoporosis, you should take calcium and vitamin D every day.
• In vitro fertilization (IVF). If you have POI and you wish to become pregnant, you may consider trying IVF.
• Regular physical activity and a healthy body weight.Getting regular exercise and controlling your weight can lower your risk for osteoporosis and heart disease.
• Treatments for associated conditions. If you have a condition that is related to POI, it is important to treat that as well. Treatments may involve medicines and hormones.

NIH: National Institute of Child Health and Human Development