According to the team, the woman was 25 when she was diagnosed as having primary ovarian insufficiency. Although she underwent hormone treatment, ovulation did not occur. She had laparoscopic surgery to remove her ovaries when she was 29.
The team cut the ovarian tissue into 1-centimeter pieces, froze them and thawed them three months later, when the woman had recovered from the surgery. They then fragmented them into 1-millimeter pieces and cultivated them in a special culture solution into pre-egg cells. These were then transplanted beneath the serosa covering the woman's fallopian tube.
The ovum, having then matured inside the woman, was removed to be fertilized in vitro with her husband's sperm.
The embryo was transplanted into the woman, and she gave birth to a healthy boy weighing about 7 pounds last winter.
Kawamura said he hopes to also conduct clinical research involving the method on women whose ovarian functions have declined with age.
Iwaho Kikuchi, associate professor of Juntendo University, said, "It's a blessing the woman gave birth following treatment involving frozen ovary tissue.
"However, doctors need to try this in a number of cases to determine whether this can actually improve the number of babies carried to term."
At least 100,000 women are believed to be suffering from primary ovarian insufficiency, or POI, nationwide. They start to show menopausal symptoms before the age of 40, and due to the deficiency of egg-bearing ovarian follicles, they become infertile. Hormone treatment has been the standard option for these women, but it is still difficult for many of them to get pregnant and carry a baby to term. For women outside of Japan, receiving an egg donated by another woman is a common practice.