Also Known As
Formal Name
Follicle-stimulating Hormone, serum or urine
This article was last reviewed on
This article waslast modified on September 23, 2019.
At a Glance
Why Get Tested?

To evaluate fertility issues, function of reproductive organs (ovaries or testicles), or pituitary function

In children, to evaluate early or delayed sexual maturation (puberty)

When To Get Tested?

For women, when you are having difficulty getting pregnant or are having irregular or absence of menstrual periods

For men, when your partner cannot get pregnant, or you have a low sperm count, low muscle mass or decreased sex drive

When your healthcare practitioner thinks that you have symptoms of a pituitary disorder or hypothalamic disorder

When a healthcare practitioner suspects that a child has delayed or earlier than expected sexual maturation

Sample Required?

A blood sample drawn from a vein in your arm; sometimes a random urine sample or 24-hour urine collection may be taken

Test Preparation Needed?

None, but the timing of a woman's sample will be correlated with her menstrual cycle.

You may be able to find your test results on your laboratory's website or patient portal. However, you are currently at Lab Tests Online. You may have been directed here by your lab's website in order to provide you with background information about the test(s) you had performed. You will need to return to your lab's website or portal, or contact your healthcare practitioner in order to obtain your test results.

Lab Tests Online is an award-winning patient education website offering information on laboratory tests. The content on the site, which has been reviewed by laboratory scientists and other medical professionals, provides general explanations of what results might mean for each test listed on the site, such as what a high or low value might suggest to your healthcare practitioner about your health or medical condition.

The reference ranges for your tests can be found on your laboratory report. They are typically found to the right of your results.

If you do not have your lab report, consult your healthcare provider or the laboratory that performed the test(s) to obtain the reference range.

Laboratory test results are not meaningful by themselves. Their meaning comes from comparison to reference ranges. Reference ranges are the values expected for a healthy person. They are sometimes called "normal" values. By comparing your test results with reference values, you and your healthcare provider can see if any of your test results fall outside the range of expected values. Values that are outside expected ranges can provide clues to help identify possible conditions or diseases.

While accuracy of laboratory testing has significantly evolved over the past few decades, some lab-to-lab variability can occur due to differences in testing equipment, chemical reagents, and techniques. This is a reason why so few reference ranges are provided on this site. It is important to know that you must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."

For more information, please read the article Reference Ranges and What They Mean.

What is being tested?

Follicle-stimulating hormone (FSH) is a hormone associated with reproduction and the development of eggs in women and sperm in men. This test measures FSH in the blood or urine.

FSH is made by the pituitary gland, a grape-sized organ located at the base of the brain. Control of FSH production is a complex system involving the hypothalamus in the brain, the pituitary gland, and the hormones produced by the ovaries or testicles. The hypothalamus releases gonadotropin-releasing hormone (GnRH), which stimulates the pituitary to release FSH and luteinizing hormone (LH), a closely related hormone also involved in reproduction.

  • In women, FSH stimulates the growth and maturation of eggs (follicles) in the ovaries during the follicular phase of the menstrual cycle. The menstrual cycle is divided into the follicular and the luteal phases, with each phase lasting about 14 days. During this follicular phase, FSH initiates the production of estradiol by the follicle, and the two hormones work together in the further development of the egg follicle. Near the end of the follicular phase, there is a surge of FSH and luteinizing hormone. Release of the egg from the ovary (ovulation) occurs shortly after this surge of hormones. The hormone inhibin as well as estradiol and progesterone help control the amount of FSH released by the pituitary gland. FSH also facilitates the ability of the ovary to respond to LH.

    As a woman ages and menopause approaches, ovarian function wanes and eventually ceases. As this occurs, FSH and LH levels rise.

  • In men, FSH stimulates the testicles to produce mature sperm and also promotes the production of androgen binding proteins. FSH levels are relatively constant in men after puberty.
  • In infants and children, FSH levels rise shortly after birth and then fall to very low levels by 6 months in boys and 1-2 years in girls. Concentrations begin to rise again before the beginning of puberty and the development of secondary sexual characteristics.

Disorders affecting the hypothalamus, pituitary, and/or the ovaries or testicles can cause the production of too much or too little FSH, resulting in a variety of conditions such as infertility, abnormal menstrual cycles, or early (precocious) or delayed sexual maturation (puberty).

How is the sample collected for testing?

A blood sample is drawn by needle from a vein in the arm. Sometimes, a random urine sample is collected but, due to the cyclic secretion of FSH, a 24-hour collection of urine may be requested. By measuring FSH levels produced over a 24-hour period, the variation in FSH levels seen throughout the day can be minimized.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed, but a woman's sample should be collected at specific times during her menstrual cycle.

Accordion Title
Common Questions
  • How is it used?

    The test for follicle-stimulating hormone (FSH), a hormone associated with reproduction and the development of eggs in women and sperm in men, has several uses.

    In both women and men, the test may be used with other hormone tests such as luteinizing hormone (LH), testosterone, estradiol, and/or progesterone to help:

    • Determine the cause of infertility
    • Diagnose conditions associated with dysfunction of the ovaries or testicles
    • Aid in the diagnosis of pituitary or hypothalamus disorders, which can affect FSH production

    In women, FSH levels are also useful in:

    • The investigation of menstrual irregularities
    • Predicting onset or confirmation of menopause

    In men, FSH levels are used to help determine the reason for a low sperm count.

    In children, FSH and LH are used to help diagnose delayed or precocious (early) puberty. Irregular timing of puberty may be an indication of a more serious problem involving the hypothalamus, the pituitary gland, the ovaries or testicles, or other systems. The measurement of LH and FSH may differentiate between benign symptoms and true disease. Once it is established that symptoms are a result of true disease, further testing can be done to discern the underlying cause.

  • When is it ordered?

    For a woman, an FSH test may be ordered when she is having difficulty getting pregnant or has irregular or an absence of menstrual periods.

    FSH may be ordered when a woman's menstrual cycle has stopped or become irregular, to determine if the woman has entered menopause.

    For a man, the test may be ordered when his partner cannot get pregnant, when he has a low sperm count, or when he has low muscle mass or decreased sex drive, for example.

    In both women and men, testing may be ordered when a health practitioner suspects that a pituitary disorder is present. A pituitary disorder can affect the production of several different hormones, so there may be signs and symptoms in addition to some of those listed above. They can include fatigue, weakness, unexplained weight loss, and decreased appetite to name a few.

    In children, FSH and LH may be ordered when a boy or girl does not appear to be entering puberty at an appropriate age (either too late or too soon). Signs of puberty may include:

    • Breast enlargement in girls
    • Growth of pubic hair
    • Growth of the testicles and penis in boys
    • Beginning of menstruation in girls
  • What does the test result mean?

    Results of an FSH test are typically considered with results of other hormone tests, such as LH , estrogens, and/or testosterone.

    As part of an infertility workup, a high or low FSH is not diagnostic but provides a piece of information on what may be the cause. For example, a hormone imbalance may affect a woman's menstrual cycle and/or ovulation. A health practitioner will consider all the information from the workup to establish a diagnosis. See the Infertility article for more on this.

    In Women

    FSH and LH levels can help to differentiate between primary ovarian failure (failure of the ovaries themselves) and secondary ovarian failure (failure of the ovaries due to disorders of either the pituitary or the hypothalamus).

    High levels of FSH and LH are consistent with primary ovarian failure. Some causes of primary ovarian failure are listed below.

    Developmental defects:

    • Failure to develop ovaries (ovarian agenesis)
    • Chromosomal abnormality, such as Turner syndrome
    • Defect in the steroid production by the ovaries, such as 17 alpha hydroxylase deficiency

    Premature failure of the ovaries due to:

    Chronic failure to ovulate (anovulation) due to:

    When a woman enters menopause and her ovaries stop working, FSH levels will rise.

    Low levels of FSH and LH are consistent with secondary ovarian failure due to a pituitary disorder or hypothalamic problem. Low FSH serum levels have been associated with increased risk of ovarian cancer.

    In Men

    High FSH levels are due to primary testicular failure. This can be the result of developmental defects in testicular growth or to testicular injury, as indicated below.

    Developmental defects:

    Testicular failure:

    • Viral infection (mumps)
    • Trauma
    • Radiation exposure
    • Chemotherapy
    • Autoimmune disease
    • Germ cell tumor

    Low levels are consistent with pituitary or hypothalamic disorders. See the article on Pituitary Disorders for more information.

    In Children

    High levels of FSH and LH with the development of secondary sexual characteristics at an unusually young age are an indication of precocious puberty. This is much more common in girls than in boys. This premature development is usually due to a problem with the central nervous system and can have a few different underlying causes. Examples include:

    • Central nervous system tumor
    • Brain injury, trauma
    • Inflammation within the central nervous system (e.g. meningitis, encephalitis)
    • Brain surgery

    Normal prepubescent levels of LH and FSH in children exhibiting some signs of pubertal changes may indicate a condition call "precocious pseudopuberty." The signs and symptoms are brought on by elevated levels of the hormones estrogen or testosterone. This may be caused by:

    • Hormone-secreting tumors
    • Adrenal gland tumors
    • Ovarian tumors or cysts
    • Testicular tumors

    Normal FSH and LH levels with a few signs of puberty can also be a benign form of precocious puberty with no underlying or discernable cause or may just be a normal variation of puberty.

    In delayed puberty, LH and FSH levels can be normal or below what is expected for a youth within this age range. Some of the causes for delayed puberty can include:

    • Dysfunction of the ovaries or testicles
    • Hormone deficiency
    • Turner syndrome
    • Klinefelter syndrome
    • Chronic infections
    • Cancer
    • Eating disorder (anorexia nervosa)
  • Is there anything else I should know?

    FSH results can be increased with use of certain drugs, including cimetidine, clomiphene, digitalis, and levodopa. FSH results can be decreased with oral contraceptives, phenothiazines, and hormone treatments. FSH will also be low when women are pregnant. A recent nuclear medicine scan may interfere with results of the FSH test if it is measured by a radioimmunoassay, which is seldom used any more.

  • I’m having a hard time getting pregnant. What tests do I need?

    Basic tests for infertility often include measuring FSH and luteinizing hormone (LH) levels. Your healthcare provider may also ask you to keep track of your body temperature, which rises slightly during ovulation. Other hormonal tests as well as a postcoital (after intercourse) examination may be done. A hysterosalpingogram (image of fallopian tubes) may be ordered to see whether your fallopian tubes are blocked. Your partner may be asked to give a specimen of semen for analysis.

  • Why would a woman have multiple FSH tests done and a man only have one?

    Multiple FSH tests may be performed for a woman in order to track FSH concentrations over time. In women, concentrations of FSH are cyclic, peaking each month; men have more stable values.

  • Why would a man need a test for FSH and LH; I thought these were female hormones?

    Men also produce FSH and LH. These hormone levels are important for male reproduction too. In men, FSH stimulates the testicles to produce sperm just as in women FSH stimulates the ovaries to produce eggs. In men, LH can be measured if testosterone levels are low.

  • Is there a home test for FSH?

    Yes. There is an FDA-approved self-test that measures the level of FSH in a urine sample. It is used as an indicator of perimenopause, which is associated with a rise in FSH levels. For more information, visit the article on Home Tests and this FDA web site.

View Sources

Sources Used in Current Review

Lin, J. (Updated 2012 February 16). Follicle-Stimulating Hormone (FSH). Medscape Reference [On-line information]. Available online at through Accessed April 2014.

Jabbour, S. (Updated 2012 January 3). Follicle-Stimulating Hormone Abnormalities. Medscape Reference [On-line information]. Available online at through Accessed April 2014.

Coney, P. (Updated 2014 April 7). Menopause. Medscape Reference [On-line information]. Available online at [On-line information]. Available online at through Accessed April 2014.

Meikle, A. and Straseski, J. (Updated 2013 November). Infertility. ARUP Consult [On-line information]. Available online at through Accessed April 2014.

Bielak, K. and Popat, V. (Updated 2012 June 5). Amenorrhea. Medscape Reference [On-line information]. Available online at through Accessed April 2014.

Hernandez-Rey, A. (Updated 2013 December 2). Anovulation. Medscape Reference [On-line information]. Available online at [On-line information]. Available online at through Accessed April 2014.

(© 1995–2014). FSH. Mayo Clinic Mayo Medical Laboratories [On-line information]. Available online at through Accessed April 2014.

Pagana, K. D. & Pagana, T. J. (© 2011). Mosby's Diagnostic and Laboratory Test Reference 10th Edition: Mosby, Inc., Saint Louis, MO. Pp 649-651.

Clarke, W., Editor (© 2011). Contemporary Practice in Clinical Chemistry 2nd Edition: AACC Press, Washington, DC. Pp 471-479.

(Updated September 9, 2013) National Institutes of Health Office of Rare Diseases Research. Klinefelter Syndrome. Available online at through Accessed April 2014.

(Updated June 18, 2012) National Institutes of Health Office of Rare Diseases Research. Turner Syndrome. Available online at through Accessed April 2014.

Sinha, S. (Updated 2013 August 14). Precocious Pseudopuberty. Medscape Reference [On-line information]. Available online at through Accessed April 2014.

Kaplowitz, P. (Updated 2013 February 11). Precocious Puberty. Medscape Reference [On-line information]. Available online at through Accessed April 2014.

Sources Used in Previous Reviews

Corbett, JV. Laboratory Tests & Diagnostic Procedures with Nursing Diagnoses, 4th ed. Stamford, Conn.: Appleton & Lang, 1996. Pp 429-431, 726.

Clinical Guide to Laboratory Tests. 3rd ed. Tietz N, ed. Philadelphia: W.B. Saunders & Co; 1995: 248-249, 210-211.

The InterNational Council on Infertility Information Dissemination, PCOS in Pediatrics: When and How Does it Start? Originally written and presented by Silva Arslanian, MD, Children's Hospital of Pittsburgh, Pittsburgh, PA; summarized in online version by Christine M. Schroeder, PhD. Available online at through

Gonadotropins: Luteinizing and Follicle Stimulating Hormones. Available online at through

Blondell RD, Foster MB, Kamlesh CD. Disorders of Puberty. American Family Physician, July 1999 (online publication). Available online at through

Hormone Society. Fact Sheet on Female Infertility. Available online at through

The Hormone Foundation. Fact sheet on Polycystic Ovary Syndrome (PCOS). Available online at through

Laurence M. Demers, PhD. Distinguished Professor of Pathology and Medicine, The Pennsylvania State University College of Medicine, The M. S. Hershey Medical Center, Hershey, PA.

A Manual of Laboratory & Diagnostic Tests. 6th ed. Fischbach F, ed. Philadelphia: Lippincott Williams & Wilkins; 2000.

Pagana K, Pagana T. Mosby's Manual of Diagnostic and Laboratory Tests. St. Louis: Mosby; 1998.

Davis B, Mass D, Bishop M. Principles of Cinical Laboratory Utilization and Consultation. Saunders; 1999.

Thompason, Sharon. LH response to GnRH. (Updated Aug 2005) MedlinePlus (online information). Available at

Neely EK, Wilson DM, Lee PA, Stene M, Hintz RL (July 1995). Spontaneous serum gonadotropin concentrations in the evaluation of precocious puberty. J Pediatric 127(1):47-52 from PubMed. Available online at through

Nirupama Kakarla, M.D.; Karen D. Bradshaw, M.D. (Posted 03/05/2004.) Disorders of Pubertal Development: Precocious Puberty. From Seminars in Reproductive Medicine 21(4):339-351 from Medscape. Available online at through

Brito VN, Batista MC, Borges MF, Latronico AC, Kohek MB, Thirone AC, Jorge BH, Arnhold IJ, Mendonca BB. (1999 Oct) Diagnostic value of fluorometric assays in the evaluation of precocious puberty. J Clin Endocrinol Metab. 84(10):3539-44. Available online through

Sheehan, M (Dec 2003). Polycystic Ovarian Syndrome: Diagnosis and Management. Clinical Medicine and Research, 2(1): 13-27. Available online at through

Pagana, K. D. & Pagana, T. J. (© 2007). Mosby's Diagnostic and Laboratory Test Reference 8th Edition: Mosby, Inc., Saint Louis, MO. Pp 629-631.

Wu, A. (© 2006). Tietz Clinical Guide to Laboratory Tests, 4th Edition: Saunders Elsevier, St. Louis, MO. Pp 412-416.

Storck, S. (Updated 2009 September 2). FSH. MedlinePlus Medical Encyclopedia [On-line information]. Available online at Accessed February 2010.

Jabbour, S. (Updated 2009 June 15). Follicle-Stimulating Hormone Abnormalities. eMedicine [On-line information]. Available online at through Accessed February 2010.

Meikle, A. W. et. al. (Updated 2009 November). Amenorrhea. ARUP Consult [On-line information]. Available online at through Accessed February 2010.

Brzyski, R. and Jensen, J. (Revised 2007 March) Female Reproductive Endocrinology, Introduction. Merck Manual for Healthcare Professionals [On-line information]. Available online at through Accessed February 2010. Menopause. Available online at through Accessed February 2010.

National Institute on Aging: Menopause. Available online at through Accessed February 2010.

MedlinePlus Health Topics: Female Reproductive System. Available online at through Accessed February 2010.

Clarke, W. and Dufour, D. R., Editors (© 2006). Contemporary Practice in Clinical Chemistry: AACC Press, Washington, DC. Pp 360-361.

Helzisouer KJ, Alberg AJ, Gordon GB, et al. Serum gonadotropins and steroid hormones and the development of ovarian cancer. JAMA 274(24):1926-1930, 1995.

Backer LC, Rubin CS, Kieszak SM, et al. Serum follicle stimulating hormone and national health and nutrition examination survey (NANES III, 1988-1994). Menopause 6(1):29-35, 1999.

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