Myth of Limited Oocytes in Women

Stem Cells Found in Ovaries

For over fifty years the science of fertility in women has been unchallenged. A woman will go though menopause and cease to be able to bear a child from her own eggs. Only recently over the past few years has it come to light that men’s reproductive organs produce less sperm with age. 

Jonathon Tilly and his research team at the Massachusetts hospital have discovered stem cells in the ovaries of mice responsible for developing follicles containing eggs and the surrounding cells who nourish the eggs. Tilly came to the conclusion that something must be going on when he calculated the amount of eggs adult mice were losing per day. 

In comparison, the remaining egg amount was more then expected. Green fluorescent protein was used as a marker to determine what was happening inside of the mice ovaries. The green glowing eggs led them to a niche where stem cells were producing immature eggs. They were located in the ovaries where most scientists had previously never thought to look. This breakthrough would begin a path of dispelling the belief that women are born with all their eggs. 

It might help to ease the mind of a ravaged cancer victim who may benefit from regenerating egg stem cells as long as all the stem cells aren’t destroyed by treatment.The Tilly team hard at work soon noticed every time a cancer patient received a bone marrow transplant shortly after the recipient became fertile again. The theory was the bone marrow carries a specific type of stem cell the ovaries use to replenish the egg supply. The bone marrow received from the donor carries these stem cells. Fertility is now restored in the cancer victim.

Another research team set out to uncover their own findings about eggs from bone marrow stem cells. They came to the conclusion using mice joined together by the skin of their legs in order to mingle their circulatory system and green fluorescent protein that the bone marrow theory was untrue. The finding does not darken the optimistic Tilly. His study had been on immature eggs not ovulated eggs of the ovary.