Testosterone is primarily produced in the Leydig cells of the testes in males, accounting for about 95% of the body's testosterone production

. In females, testosterone is produced in smaller amounts mainly by the ovaries and adrenal glands

. Additionally, the adrenal glands produce precursors like dehydroepiandrosterone (DHEA), which the body can convert into testosterone

. The production process is regulated by the brain: the hypothalamus releases gonadotropin-releasing hormone (GnRH), which signals the pituitary gland to release luteinizing hormone (LH). LH then stimulates the Leydig cells in the testes to convert cholesterol into testosterone

. In summary:

• In men: Testosterone is mainly produced in the Leydig cells of the testes (about 95%), with a small contribution (around 5%) from the adrenal glands.
• In women: Testosterone is produced by the ovaries and adrenal glands in much smaller quantities.
• Regulation: The hypothalamus and pituitary gland control testosterone production via hormonal signals (GnRH and LH).

This hormone is then released into the bloodstream to act on various tissues throughout the body