- Red or tiger top tube
- 5 mL of venous blood
- Some sources recommended 3 blood draws 60 minutes apart
Additional information
- In female patients, indicate the phase of the menstrual cycle or duration of menopause on the lab request
- Handle sample gently to prevent hemolysis
- Medications containing estrogen and progesterone should be discontinued 4 weeks before test
- Follicle Stimulating Hormone (FSH) is a glycoprotein gonadotropin hormone synthesized and stored in the anterior pituitary gland
- FSH is regulated by hypothalamic gonadotropin-releasing hormone and by gonadal sex hormones, such as estrogen and progesterone in females, and testosterone in males
- In females, FSH promotes maturation of the graafian (germinal) follicle causing estrogen secretion and allowing the ovum to mature in conjugation with Luteinizing Hormone (LH)
- In males, FSH stimulates testicular development and acts on sertoli cells of the testis to induce spermatogenesis
- FSH acts synergistically with LH for reproduction
- The clinical utility of FSH testing includes:
- Evaluation of menstrual disorders such as amenorrhea
- Evaluation of precocious puberty in girls below the age of 9 yrs and in boys below 10 yrs of age
- Evaluate failure of sexual maturation in adolescence
- Assist in distinguishing between primary and secondary (pituitary or hypothalamic) gonadal failure
- Aid in the diagnosis and treatment of infertility
- To evaluate ovarian reserve of egg supply in females
- To evaluate low sperm count in males
- Aids in differential diagnosis of hypogonadism
- Evaluation of ambiguous sexual differentiation in infants
- Assist in the diagnosis of impotence and gynecomastia
- The symptomatology as a result of abnormal levels of FSH in males includes:
- Low FSH levels
- Erectile dysfunction
- Decreased libido
- Infertility
- Low energy
- Anosmia (Kallmann syndrome)
- Ambiguous genitalia at birth
- Failure to undergo or complete puberty at adolescence
- Visual abnormalities, headaches (mass or a destructive process involving the pituitary)
- High FSH levels
- Precocious puberty in children
- Headaches, visual impairment, hormonal deficiencies (mass effect of gonadotroph adenoma)
- The symptomatology as a result of abnormal levels of FSH in females include:
- Low FSH levels (as a result of secondary ovarian failure)
- Delayed puberty
- Irregular menstruation
- Infertility
- High FSH levels (as a result of either prolonged hypoestrogenism or primary ovarian failure)
- Hot flashes and sweats
- Irritability
- Dry skin
- Dry eyes
- Vaginal dryness
- Dyspareunia
- Decreased libido
- Decreased energy
- Oligomenorrhea
- Amenorrhea
Additional information
- In menstruating women FSH levels spike at midcycle
- FSH production is pulsatile, episodic, and cyclic, and is subject to diurnal variation
- Normally day to day variation is about 40%
- Factors interfering with test results include:
- Hormone medications such as testosterone, estrogen, and progesterone
- Radioactive scan performed within 1 wk before test
- Heavy cigarette smoking
- Hemolyzed specimens
- Related laboratory tests include:
- Clomiphene challenge test
- Cortisol (Free or Serum)
- Creatinine
- Estradiol
- Karyotyping
- Luteinizing hormone
- Pregnancy test
- Progesterone
- Prolactin
- Serum electrolytes
- Serum glucose
- Testosterone
- Thyroid stimulating hormone
Consult your laboratory for their normal ranges as these may vary somewhat from the ones listed below.
| Conv. Units (mIU/L) | SI Units (IU/L) | |
|---|---|---|
| Male (Adult) | 1-18 | 1-18 |
| Female (Adult) | ||
| Follicular phase | 2-15 | 2-15 |
| Ovulatory peak | 15-50 | 15-50 |
| Luteal phase | 1-15 | 1-15 |
| Postmenopausal | 20-120 | 20-120 |
| Children (Prepuberty) | <10 | <10 |
Conditions associated with increased FSH levels include:
- Congenital
- Turner's syndrome
- Klinefelter's syndrome
- Mutation in FSH receptor gene in men
- Cryptorchidism
- Disorders of androgen biosynthesis
- Sertoli-Cell-Only syndrome
- End organ resistance to androgens, as in androgen receptor defects or Reifenstein's syndrome
- Anorchia (testicular agenesis)
- Myotonic dystrophy
- Acquired
- Infections such as orchitis
- Radiation exposure
- Antineoplastic agents
- Trauma to seminiferous tubules and Leydig cells
- Testicular torsion (>8 hrs)
- Ovarian agenesis and dysgenesis
- Ovariectomy
- Menopause and menstrual disorders
- Sheehan's syndrome
- Hypogonadism
- Hyperpituitarism
- Precocious puberty, either idiopathic or secondary to a CNS lesion
- Castration
- Complete testicular feminization syndrome
- Autoimmune damage
- Drugs and substances
- Bicalutamide
- Bromocriptine
- Cimetidine
- Clomiphene
- Danazol
- Dibromodichloropropane
- Erythropoietin
- Gonadotropin-releasing hormone
- Growth hormone-releasing hormone
- Hydrocortisone
- Ketoconazole
- Levodopa
- Metformin
- Naloxone
- Nilutamide
- Phenytoin
- Suramin
Conditions associated with low FSH levels, include:
- Congenital
- Idiopathic hypogonadotropic hypogonadism
- Failure of hypothalamus to function properly (Kallmann's syndrome)
- Craniopharyngioma
- Combined pituitary hormone deficiency
- Fertile eunuch syndrome
- Abnormal beta subunit of FSH
- Acquired (secondary hypogonadism)
- Mass lesions
- Pituitary or hypothalamic tumors
- Metastatic cancer to the sella from adrenal, ovary, and testis
- Hypothalamic or pituitary surgery
- Hypothalamic or pituitary radiation
- Infiltrative lesions
- Hemochromatosis
- Histiocytosis
- Lymphoma
- Sarcoidosis
- Lymphocytic hypophysistis
- Infections as in tuberculous meningitis
- Pituitary apoplexy
- Trauma with damage to pituitary
- Glucocorticoid excess
- Endogenous, as in Cushing’s syndrome
- Exogenous due to drugs (given below)
- Hyperprolactinemia
- Renal insufficiency
- Liver insufficiency
- Primary hypothyroidism
- Drugs (neuroleptics)
- Critical illness
- Myocardial infarction
- Surgery
- Sex steroid secreting tumors
- Feminizing and masculinizing ovarian tumors
- Polycystic ovarian disease
- Empty sella
- Pituitary infarction
- Chronic systemic disease
- AIDS
- Chronic renal failure
- Cirrhosis
- Adrenal hyperplasia
- Acute alcohol ingestion
- Excessive exercise in men
- Anorexia nervosa
- Obesity
- Malnutrition
- Drugs
- Anabolic steroids
- Anticonvulsants
- Carbamazepine
- Conjugated estrogens
- Corticotropin-releasing hormone
- Diethylstilbestrol
- Estrogen/progestin therapy
- Finasteride
- Goserelin
- Leuprolide
- Medroxyprogesterone
- Megestrol
- Octreotide
- Oral contraceptives
- Phenothiazines
- Pimozide
- Prednisone
- Stanozolol
- Tamoxifen
- Toremifene
- Valproic acid
- Alan AA et al. Reliability of follicle-stimulating hormone measurements in serum. Reproductive Biology and Endocrinology 2003, 1:49. doi:10.1186/1477-7827-1-49
- ARUP Laboratories®. Follicle Stimulating Hormone, Serum. [Homepage on the internet]©2007. Last accessed on April 23, 2007. Available at URL: http://www.aruplab.com/guides/ug/tests/0070055.jsp
- eMedicine®. Follicle-Stimulating Hormone Abnormalities. [Homepage on the Internet]© 1996-2006 by WebMD. Last updated on January 13, 2006. Last accessed on April 23, 2007. Available at URL: http://www.emedicine.com/med/topic803.htm
- Iqbal J et al. Follicle-stimulating hormone stimulates TNF production from immune cells to enhance osteoblast and osteoclast formation. Proc Natl Acad Sci U S A. 2006 Oct 3;103(40):14925-30. Epub 2006 Sep 26.
- LabTestsOnline®. FSH. [Homepage on the Internet]© 2001-2006. Last reviewed on April 23, 2007. Last accessed on October 11, 2006. Available at URL: http://www.labtestsonline.org/understanding/analytes/fsh/test.html
- Letterie GS et al. Assessment of ovarian reserve by using the follicle-stimulating hormone isoform distribution pattern to predict the outcome of in vitro fertilization. Fertil Steril. 2006 Sep 22; [Epub ahead of print].
- Rosano GM et al. Low testosterone levels are associated with coronary artery disease in male patients with angina. Int J Impot Res. 2006 Aug 31; [Epub ahead of print].
- UTMB Laboratory Survival Guide®. Folate, serum. [Homepage on the Internet]© 2006. Last reviewed in February 2006. Last accessed on April 23, 2007. Available at URL: http://www.utmb.edu/lsg/LabSurvivalGuide/chem/fsh.htm
- van Wely M et al. Validation of a prediction model for the follicle-stimulating hormone response dose in women with polycystic ovary syndrome. Fertil Steril. 2006 Oct 3. [Epub ahead of print].