[–] ProxyMusic 8 points Edited

If any of this were true, then all males who produce testosterone from their testes - as they all do as fetuses, babies, adolescents and adults - would be having "tranz periods" all the time. Because males automatically convert some of their endogenous testosterone to estrogen through aromatization on a continual basis.

It is important to note that estrogen and testosterone are not opposites of one another – the relationship is more complex than that. Testosterone, as the predominant male sex hormone, is integral for male sexual development (particularly during adolescence), accounting for the emergence of the male characteristics of increased facial and body hair, muscle mass and definition, and changes to a lower, deeper voice. Testosterone is produced primarily in the testicles and is associated with key body functions, including bone density, fat metabolism and distribution, muscle mass and strength, red blood cell production, sperm production, and libido.

Estrogen is also essential for male sexual development and overall optimal male health, because it too plays an important role in maintaining healthy function of practically every system in the body, including the neurological, cardiovascular, musculoskeletal, and immune systems. Men typically produce estrogen from the breakdown of testosterone by the aromatase enzyme (also known as estrogen synthase or estrogen synthetase). Aromatase is present in fat tissue, the adrenal glands, the brain, and the testicles.


XY persons with the disorder of male sex development CAIS have very high levels of estrogen because they convert ALL their T into estrogen, and their testes often make such massive amounts of T that their T levels are well above the normal male range (some persons with CAIS have been found to have T levels of 50-70 nmol/L when the normal male range tops at at just under 30 nmol/L). Yet people with CAIS do not customarily claim - or AFAIK ever claim - to have periods or anything resembling periods.