How long does meiosis take?

Meiosis takes different times to complete depending on the gametes being formed. Gametogenesis is the process of the formation of sperm (spermatogenesis) and eggs (oogenesis). Spermatogenesis takes approximately 64 days to complete. During this process, diploid spermatogonia first undergoes mitosis, leading to the formation of a primary spermatocyte. This primary spermatocyte goes through a meiotic division to produce two haploid secondary spermatocytes. The secondary spermatocytes then undergo another meiotic division to form two spermatids. The spermatids over time grow flagella and develop into mature sperm cells. A total of 4 sperm cells are formed from each primary spermatocyte that undergoes meiosis. 

Oogenesis is completed in 12 days. A diploid oogonium first undergoes mitosis until it develops into a primary oocyte. This initiates the first meiotic division, but pauses in its process. It then completes the division as it grows in the follicle and forms a haploid secondary oocyte. The secondary oocyte initiates the second meiotic division and also pauses its process. It does complete the second division until it is fertilized by a sperm cell. Once fertilization occurs, a mature ovum is formed. Only a single ovum is formed from a single primary oocyte.