Definition 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 doctor suspects a problem with:
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 After the needle is withdrawn, the puncture site is covered for a short time to prevent bleeding.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.
What is involved in preparation for the test? There is generally no preparation for this test. However, the doctor may want to have the test done during a particular time of a woman's menstrual cycle.
What do the test results mean? Normal values depend upon the sex of the person and other factors. Greater than normal levels of FSH may be found in the following conditions:
polycystic ovary disease, a condition that causes ovarian cysts and menstrual cycle problems or irregularities
Author: Eva Martin, MD Reviewer: eknowhow Medical Review Panel Editor: Dr John Hearne Last Updated: 6/06/2005 Contributors Potential conflict of interest information for reviewers available on request
