FSH refers to Follicle Stimulating Hormone. FSH is produced by the pituitary gland, and carried into the ovaries to stimulate the follicles. When FSH levels rise, some of the eggs will respond with low levels of oestradiol. Once this occurs, the ovaries communicate back to the pituitary gland that the egg follicles have been stimulated and FSH production slows down.
If the supply of egg follicles is low and they don’t respond to stimulation, the pituitary gland tries to make up for it by y producing more FSH every month. When this happens, the overall levels of FSH rise.
If you are under 40 years of age and have had no periods for some time, elevated FSH levels may be a sign of premature ovarian failure. A single showing of high FSH levels with a normal menstrual cycle is not conclusive because FHS levels can fluctuate. Also, high levels may indicate resistant ovary syndrome rather than premature ovarian failure.
Abnormal FSH levels can also predict a poor response to fertility medication. It can also predict a low chance for successful pregnancy when using in vitro fertilization.