Now this entire foundation of knowledge regarding female egg production and depletion is in question. A recent paper by Johnson et al., (Nature, March11th 2004, Vol. 428, pp. 145-150) has opened up new doors for a drastic revision of the biological theory behind female egg production, and thus her fertility.
The research comes from the laboratory of Jonathan Tilly, an established and highly respected developmental biologist at Harvard Medical School. By studying mice, the researchers determined that germ cells persist after birth; and such stem cells give rise to new eggs throughout a mouse's life.
In a remarkably simple experiment, researchers quantified the rate of egg depletion in the mouse ovaries, and determined that the rate should have exhausted the egg supply much earlier. Yet an unidentified replenishment was taking place. Mice are normally fertile for about a year, but Tilly found that their egg supply would be exhausted in just 2 weeks if it were not somehow being replenished.
Full article: http://www.infertilitydoctor.com/fertilityflash/vol2_issue4.htm
