Where are sperm produced?
Sperm are produced in the seminiferous tubules of the testes.
The structure and overall function of the testes are regulated by endocrine glands in the hypothalamus and pituitary gland. In addition, local autocrine and paracrine regulatory mechanisms within the testes play a crucial role in modulating spermatogenesis.

Spermatogenesis begins with the differentiation of spermatogonial stem cells and ends with the formation of mature spermatozoa. Differentiating germ cells are arranged in a highly organized, spatially specific pattern within the seminiferous tubules—this orderly progression constitutes spermatogenesis.
It takes approximately 45 days for spermatogonia to develop into morphologically mature, tadpole-shaped spermatozoa. However, at this stage, sperm are not yet fully functional and lack fertilizing capacity. They must be stored in the epididymis for an additional period—typically 30 to 50 days—to complete their final maturation and acquire the ability to fertilize an oocyte.
Thus, the sperm present in a man’s ejaculate began developing about three months earlier, attained their characteristic morphology approximately one and a half months prior, and achieved full functional maturity shortly before ejaculation.