It has been disclosed that an Osaka woman in her 40s gave birth to a baby last year using her own frozen egg in what is believed to be the first such case in Japan involving a healthy woman. In 2014, it was reported that a 30-year-old woman gave birth to a child using an egg she had frozen 12 years earlier when she was undergoing cancer treatment that could have made her unable to reproduce.

Egg-freezing technology is drawing increased interest as a growing number of working women marry and give birth at later ages. Births using frozen eggs may increase. Still, the method involves a variety of risks. If the option is being pursued because women want to put off childbirth to avoid facing problems in their jobs, it shows the need for creating a socioeconomic environment in which women can have children at a younger age without disrupting their careers so they don't feel forced to rely on technology that has a low success rate.

In the process of freezing eggs, oocytes (immature egg cells) are extracted from the woman. It used to be difficult to freeze and store oocytes because they are easily damaged compared with sperm or fertilized eggs. But recent technological advances have made egg preservation a viable option for people who need to undergo cancer or other treatment that will damage their ovaries but may want to have children in the future. Freezing their eggs certainly gives these women hope.