FSH Test

Other names: Follicle-Stimulating Hormone

FSH (follicle stimulating hormone) is produced by the pituitary gland, which is located in the brain. Hormones produced by the gonads (the ovaries in females and the testes in males), the pituitary gland and the hypothalamus are responsible for the control of the production of FSH.

In females, FSH is used to stimulate the development of the egg (the ovarian follicle); this takes place during the follicular stage of the menstrual cycle. In males, FSH stimulates the production of sperm by the testes; in adult males, levels of FSH remain constant.

When is the test used?

The test is used to measure the levels of FSH in the blood; this helps doctors to check the function of the pituitary gland and check that hormone levels are normal. The test may be used (along with other tests) to test for possible causes of both male and female infertility. The test is also useful for finding possible causes of irregular periods in women and diagnosing problems with the pituitary gland.

The test is usually ordered when a couple are having problems conceiving (usually, fertility testing is recommended for couples who have been trying to conceive for two years without any success). The FSH test can help to determine the cause if a man has a low sperm count. The test can also be used to see if a woman has started the menopause.

How is the test done?

The test is done by collecting a sample of blood from a vein in the arm; the blood is taken from a vein (usually on the inside of the elbow) using a needle; the sample is collected in a syringe and then bottled and labelled with the patient’s name. The sample is then sent off to the laboratory for testing.

What do the test results mean?

In female patients, the test results can help to determine between primary ovarian failure and secondary ovarian failure; primary failure relates to a problem with the ovary, while secondary failure relates to other health conditions which affect the pituitary gland or the hypothalamus, which impact upon the function of the ovaries. Increased levels of FSH and LH (luteinising hormone) usually indicate primary ovarian failure; this is usually caused by defects with the structure or development of the ovaries or conditions which affect ovulation, such as PCOS (polycystic ovarian syndrome) and thyroid disease. Primary ovarian failure may also be caused by radiotherapy and chemotherapy. High levels of FSH in males are usually caused by primary testicular failure; this is usually a result of developmental defects or injury to the testicles.

Low levels of FSH and LH usually indicate secondary ovarian failure; this is caused by problems with the pituitary gland.

FSH levels will rise when a woman has gone through the menopause.

Specific Blood Tests



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