What is FSH Test?
Written by Jessica Smith   
Thursday, 15 October 2009
This is a blood test that measures the amount of follicle-stimulating hormone (FSH) produced by the pituitary gland.
Who is a candidate for the test?

Fertility in men and women, as well as menstruation in women, are regulated by a complex interaction of hormones. The ovaries, pituitary gland, and hypothalamus produce these hormones. Follicle-stimulating hormone, or FSH, causes the follicles within the ovaries to mature.

FSH levels may be measured if the healthcare provider suspects a problem with:
- menopause, a time in life when menstruation stops
- ovarian cysts, which are fluid-filled sacs on the ovary
- precocious puberty, or puberty that happens at an abnormally young age
- delayed puberty, or puberty that hasn't occurred by the time it should
- female infertility, or inability to become pregnant
- male infertility, or the inability to impregnate a woman
- anovulatory bleeding, which is abnormal vaginal bleeding not related to a regular menstruation cycle
- amenorrhea, or the absence of menstruation
- testes that are absent or abnormally small

How is the test performed?

A blood sample is taken from a vein on the forearm or hand. First, the skin over the vein is cleaned with an antiseptic. Next, a strong rubber tube, or "tourniquet," is wrapped around the upper arm. This enlarges the veins in the lower arm by restricting blood flow through them. A fine needle is gently inserted into a vein, and the tourniquet is removed. Blood flows from the vein through the needle, and is collected in a syringe or vial. After the needle is withdrawn, the puncture site is covered for a short time to prevent bleeding. The blood sample is sent to the laboratory to determine the amount of FSH circulating in the blood.