Blood & Laboratory Values

Follicle Stimulating Hormone (Follitropin) – Function & Diseases

Follicle Stimulating Hormone (Follitropin)

The follicle-stimulating hormone (follitropin or FSH for short) is one of the sex hormones . In a woman it is responsible for the maturation of the egg cell or for the growth of the follicle, in a man it is responsible for the production of sperm . FSH is produced in the pituitary gland in both sexes .

What is Follicle Stimulating Hormone?

The follicle stimulating hormone is produced in the pituitary gland. Based on its name, it could be assumed that it occurs exclusively in a woman; But this is not the case.

FSH is required for follicle growth, follicle maturation and indirectly for oocyte maturation. Men need FSH for sperm formation (spermatogenesis), albeit in a comparatively small amount. FSH is therefore directly important for the fertility of both sexes. An FSH deficiency can lead to sterility or infertility .

Production, Manufacturing & Education

The female menstrual cycle is controlled by the fine interaction of different hormones . The FSH plays a central role in this. At the beginning of a new cycle, the midbrain first produces the gonadotropin-releasing hormone (GnRH for short).

GnRH stimulates the pituitary gland to produce luteotropin (LH for short) and FSH. The FSH causes the maturation of several follicles in the woman ‘s ovaries . Through its activity, it stimulates the formation of estrogen in the follicles and at the same time activates the cells inside the follicles – the granulosa cells – which in turn supply the follicles with nutrients.

In this way, egg cells mature, which under certain conditions can later be fertilized and grow into an embryo. The production of FSH stops around the 10th day of the female cycle, namely when the dominant follicle has released a mature follicle into the fallopian tube (ovulation).

A man’s pituitary gland secretes FSH continuously, albeit in small amounts. In the male body, FSH stimulates the maturation of sperm (spermatogenesis).

Function, effect & properties

FSH is an endogenous hormone that is produced in the pituitary gland. It is more directly related to a person’s fertility, since it is responsible both for the maturation of fertilizable egg cells and for spermatogenesis in men.

The production of FSH is controlled by the superordinate hormone GnRH, which is produced in the midbrain . FSH production in men remains more or less constant throughout life, ie the pituitary gland of sexually mature men continuously releases a certain amount of FSH.

The woman’s body, on the other hand, stops fertilizing around the age of 50 ( menopause ). In this phase, the midbrain will not produce GnRH and consequently production of FSH will also largely cease. Maturation of follicles and ovulation are then no longer possible; A woman can then no longer have a child naturally.

Sometimes it happens that even relatively young women do not produce any FSH or the wrong amount. A follicle can then neither form nor ovulate . A woman usually notices this when her menstrual period starts irregularly or not at all, although she is not pregnant . The lack of FSH is often responsible for polycystic ovary syndrome (PCO) .

Here the woman develops countless follicles, but due to the low FSH concentration no leading follicle is produced. Ovulation and pregnancy are then not possible. As part of fertility treatment, an FSH deficiency can be regulated by taking medication (e.g. monopreparation Fertavid®, Puregon®; combination preparation Pergoveris®).

Illnesses, Ailments & Disorders

The most obvious clinical picture of a woman suffering from FSH deficiency is her sterility, her most common complaint being an irregular menstrual cycle.

If there is an underproduction of FSH, follicles will mature in the body. However, they are not fully formed and no follicle is able to assume the leading function (polycystic ovary syndrome). The result is a disrupted menstrual cycle, since neither ovulation nor the formation and subsequent bleeding of the lining of the uterus can take place.

The woman notices irregular bleeding up to a complete absence for several months without pregnancy. Since ovulation is either irregular or not at all, the probability of becoming pregnant is low or non-existent. Women with PCOS or FSH deficiency can still have a child as part of fertility treatment.

The FSH deficiency can be compensated for with medication (eg Puregon®), so that the woman either ovulates herself or allows enough egg cells capable of fertilization to mature so that IVF can then be carried out. If your cycle is irregular and you want to have children, a doctor’s visit is always advisable.

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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.