OtherHuman1963

Spermatogenesis in man: an estimate of its duration.

Journal: Science (New York, N.Y.)Published: 1963DOI: 10.1126/science.140.3563.184

Plain-language summary

This study set out to measure how long sperm take to develop in men. The researchers injected tritiated thymidine, a radioactive marker, into the testicle, then took biopsies at intervals afterwards and tracked how far the marked cells had moved through sperm production. One cycle of the seminiferous epithelium, the tissue inside the testicle where sperm are made, lasted 16 days. The whole of sperm production was estimated at roughly 64 days.

Key findings

  • One cycle of the seminiferous epithelium lasts about 16 days.
  • The whole of sperm production is estimated at roughly 64 days.

How to analyze the study yourself

Study type
This early study used radioactive labeling to track cell development directly in human tissue, a method that can precisely time biological processes but involves invasive procedures.
Population
The paper does not describe the volunteers. The abstract says only that testicular biopsies were taken at intervals after an injection into the testicle, which is the method rather than who took part. It gives no number, no ages and no health status, and the only thing establishing they were men is the paper's title.
Funding
Not reported
Takeaway
This study found that the whole of sperm production runs roughly 64 days, which is a little over two months. If you change something to improve your sperm, it may be worth waiting a full three months before you retest, because a sample taken sooner is still reporting the conditions you had before you changed anything.