This essay was written by @Metacelsus.

In March 2023, a research team at Osaka University announced an extraordinary achievement: the production of viable eggs using cells taken from male mice.

Building on years of research into stem cells and reproductive development,1 the researchers, led by Professor Katsuhiko Hayashi, developed a method to induce male stem cells to lose their Y chromosome and duplicate the X chromosome, thus becoming female. From there, researchers took the female cells and grew eggs from them using an elaborate protocol they had initially published in 2016.

From the paper and ensuing media fanfare, a question emerged: When will this technology become available for people?

For nearly all of human history, there was only one way to make a baby. When a man and a woman love each other very much . . . well, you know the rest. But for many people, the usual [...]