Spermatogenesis takes approximately 70 days, therefore in order for sperm production to be continuous and not intermittent, multiple spermatogenic processes are occurring simultaneously within the same seminiferous tubule, with new groups of spermatogonia arising every 16 days (spermatogenic cycle).

At what age does spermatogenesis end?

Discussion and conclusion: Our study confirms that spermatogenesis is possible until a very advanced age (95 years) without any specific chromosome risk.

What is spermatogenesis and when does it start and end?

Spermatogenesis and spermiogenesis

Spermatogenesis begins with spermatogonia (the diploid (2n) immature sperm cells derived from embryonic germ cells) dividing by mitosis. ... Spermiogenesis is the final stage of spermatogenesis, and, during this phase, spermatids mature into spermatozoa (sperm cells) (Figure 2.5).