Abstract

The evolutionary and biological mechanisms underlying female reproductive aging have long been a matter of interest. Reproductive biologists have tackled with the relatively limited fertile period in female lifespan compared to male fertility that continues until the late ages. For more than five decades, it has been believed that females are born with a fixed number of germ cells that constitute ovarian follicle reserve and depletion of this reserve causes menopause. However, researchers recently reported findings that support the presence of oogenesis in postnatal mammalian ovaries, which caused a paradigm shift in our current knowledge of reproductive biology. In this minireview, we provide a brief history of one of the central dogmas in reproductive biology and subsequently present recent studies on the existence of germline stem cells in the mammalian ovary.