Seeking for hypermusculation can lead to the development of problems to conceive children, i.e. a reversible sterility.
Steroids are a group of lipid molecules whose base is cholesterol and that can be naturally found in the body. Among the sexual hormones are included the following: female hormones —estrogenic hormone and luteal hormone— and male hormones —testosterone. Among them are also included vitamin D and hormones related to stress, such as glucotiroids, cortisol, and corticosterone. These molecules turn into one another depending on the needs of the organism, which means they are related to each other.
An effect of testosterone in particular is an increasing the body mass. That is why artificial anabolic steroids have been developed, which are analogue molecules of steroids that can be taken orally or injected and provoke a rapid increase of the muscular mass. As a consequence, they have become very famous in the search for a fast increase of male muscular mass.
Steroids have reversible and irreversible side effects. Since the estrogenic hormone and the testosterone come from the same metabolic route, an increase in the estrogenic hormone instead of testosterone can take place and is not what is intended. This would result in a growth of the breasts in the men (gynecomastia), baldness, aggressiveness, or changes in the voice deepness in women.
How do steroids affect male sterility?
For the formation of the spermatozoa, the hypothalamus (located in the brain cortex) sends an order to the pituitary gland (that has the shape of a pea and is located under the cerebellum), which expels the hormones required for the spermatogenesis: LH (luteinizing hormone) and FSH (follicle-stimulating hormone).
The formation of the spermatozoa is followed by an increase in the concentration of testosterone that acts on the hypothalamus, reducing the production of LH and FSH and controlling spermatogenesis.
This means that the high concentration of testosterone acts on the hypothalamus-pituitary gland-testicle axis to stop sperm production. This happens in a natural way but when the steroids rate increases artificially, testosterone in this case, the organism detects this increase in the concentration of this hormone and receives the order of stopping spermatogenesis. This way the production of spermatozoa in the seminiferous tubules (located inside the testicles) stops. The body can’t distinguish the origin of testosterone and thus the production of spermatozoa stops, which consequently causes sterility.
The testicles stop the production of gametes and become smaller, since part of the testicular volume depends on the seminiferous tubules and the formation of spermatozoa. This hormonal alteration can be reversed by eliminating the external steroids source, but at least two months will be needed for the testicular function to return to normality.