The first human eggs grown from human stem cells could be fertilized with human sperm cells later this year, potentially adding one more peg in the ladder toward reproduction sans human interaction. In this case it would entirely bypass a woman’s donation of her eggs. But it could also turn stem cells into an infinite loop, of egg cells into embryos into stem cells, and on and on, in a fractal-like repetition of reproduction.
In February, a study was announced involving Japanese women whose reproductive stem cells were donated because they were undergoing gender reassignment surgery. Researchers at Massachusetts General Hospital were able to coax these ovarian stem cells into becoming immature human egg cells, which were then incubated in mice so they’d have the proper ovarian structures. Now these same scientists, working with a team at Edinburgh University, want to fertilize them.