Follicle-Stimulating Hormone (FSH) – Overview
Follicle-stimulating hormone (FSH) is a naturally occurring hormone that plays a key role in regulating reproductive function in both men and women.
Things worth knowing about "Follicle-Stimulating Hormone"
Follicle-stimulating hormone (FSH) is a naturally occurring hormone that plays a key role in regulating reproductive function in both men and women.
What Is Follicle-Stimulating Hormone?
Follicle-stimulating hormone (FSH) is a glycoprotein hormone produced and released by the pituitary gland, a small gland located at the base of the brain. It belongs to the group of hormones known as gonadotropins and works closely together with luteinizing hormone (LH). FSH is essential for regulating the female menstrual cycle and for supporting sperm production in men.
Function and Mechanism of Action
FSH binds to specific receptors in the gonads (ovaries and testes), triggering important biological processes:
- In women: FSH stimulates the growth and maturation of ovarian follicles, which contain the eggs. It also promotes the production of estrogen, which is necessary for the thickening of the uterine lining.
- In men: FSH supports spermatogenesis — the production of sperm in the testes — by acting on Sertoli cells.
The release of FSH is stimulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus and is regulated through a negative feedback loop involving estrogen and inhibin.
Clinical Relevance and Measurement
FSH blood levels serve as an important diagnostic marker in reproductive medicine and endocrinology. An FSH test is performed as a simple blood test and provides valuable information about the function of the ovaries or testes.
Elevated FSH Levels
Higher-than-normal FSH levels may indicate reduced gonadal function, such as in:
- Menopause or premature ovarian insufficiency in women
- Testicular dysfunction (e.g., Klinefelter syndrome) in men
- Primary gonadal insufficiency
Low FSH Levels
Lower-than-normal FSH levels may point to disorders of the hypothalamus or pituitary gland, for example in cases of:
- Hypopituitarism (underactive pituitary gland)
- Severe underweight or eating disorders
- Excessive physical stress or over-training
Reference Values
FSH reference ranges vary depending on sex, age, and cycle phase in women. Typical serum values are:
- Women (follicular phase): approx. 3–10 mIU/ml
- Women (menopause): > 25 mIU/ml
- Adult men: approx. 1.5–12 mIU/ml
Exact reference ranges may vary slightly between laboratories.
FSH in Medical Treatment
Synthetically produced FSH, known as follitropin, is used in assisted reproduction to stimulate the ovaries to produce multiple eggs — a process called ovarian stimulation. This is a key component of fertility treatments such as in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). In men with FSH deficiency, FSH therapy may help restore sperm production.
References
- Styne DM, Grumbach MM: Physiology and Disorders of Puberty. In: Williams Textbook of Endocrinology, 14th ed. Elsevier, 2020.
- World Health Organization (WHO): Laboratory Manual for the Examination and Processing of Human Semen, 6th ed. WHO Press, 2021.
- Themmen APN, Huhtaniemi IT: Mutations of Gonadotropins and Gonadotropin Receptors. Endocrine Reviews, 2000; 21(5): 551-583. PubMed PMID: 11041447.
Most purchased products
For your iron balance
Specially formulated for your iron balance with plant-based curry leaf iron, Lactoferrin CLN®, and natural Vitamin C from rose hips.
For your universal protection
As one of the most valuable proteins in the body, lactoferrin is a natural component of the immune system.
For Healthy Oral Flora & Dental Care
Formulated lozenges with Dentalac®, probiotic lactic acid bacteria, and Lactoferrin CLN®The latest entries
3 Posts in this encyclopedia categoryDietary Protein Balance
Wound healing optimization
Most read entries
3 Posts in this encyclopedia categoryMagnesiumcarbonat
Calorie content
Cologne list
Related search terms: Follicle-Stimulating Hormone-en