High FSH

Follicle stimulating hormone (FSH) is exactly what it sounds like—a hormone that stimulates follicles (the sacs within your ovaries that contain eggs) to grow.

FSH is produced by the pituitary gland which is located at the base of the brain. FSH travels into the ovaries and stimulates the follicles to produce the female hormone estrogen and produce mature eggs. When an egg matures, the follicle releases it so the egg can travel to the uterus for fertilization.

If you have a low supply of follicles and they do not respond to FSH, your pituitary gland tries to compensate by increasing FSH production every month, resulting in elevated FSH levels.

Elevated FSH levels are normal in menopausal women, who have depleted their supply of follicles capable of developing into a mature egg. In this instance, the pituitary gland produces extra FSH trying to stimulate the ovaries to produce a good follicle and produce estrogen. This monthly increased production happens for the rest of the woman’s life.

A high FSH level is not normal, however, if you are under the age of 40.

How Does High FSH Affect Fertility?

If you have an abnormally high level of FSH at a young age, it may mean you have run out of follicles. Unfortunately, your body is not able to make more. If you do not have any follicles capable of developing into a mature egg, you are unlikely to be able to get pregnant.

If you have elevated FSH levels, are under 40 years old, have not menstruated for more than six months, or have irregular bleeding, your ovaries may not be working properly. When your ovaries fail at an earlier than expected age, it is called premature ovarian failure (POF). Since loss of ovarian function results in abnormally low levels of estrogen, very few women with premature ovarian failure are able to get pregnant naturally.

Unfortunately, women who have high FSH levels often respond poorly to fertility medication or not at all. They may also have a low chance of getting pregnant when they try a type of assisted reproductive technology called in vitro fertilization (IVF, which uses an egg fertilized by sperm outside the womb) to try to achieve pregnancy. One family building option for women with high FSH is donor egg.