Researchers at Newcastle University in England report they have coaxed the first human sperm cells from embryonic stem cells, in a remarkable demonstration of how quickly the field of stem-cell ...

Katsuhiko Hayashi pulls a clear plastic dish from an incubator and slides it under a microscope. "You really want to see the actual cells, right?" Hayashi asks as he motions toward the microscope.

They're leading in the development of IVG, new fertility technology that could make sperm and eggs from practically any cell in the body. The... Japanese scientists race to create human eggs and sperm ...

Katsuhiko Hayashi, a developmental geneticist at Osaka University, is working on ways to make what he calls "artificial" eggs and sperm from any cell in the human body. (Kosuke Okahara for NPR) ...

We all know the drill for reproduction—sperm meets egg. But mice aren’t people. And the same recipe doesn’t work for human reproductive cells. One reason, according to Dr. Mitinori Saitou at Kyoto ...

The team observed the emergence of the three-dimensional embryo-like structures under a microscope in the lab. These started producing blood (seen here in red) after around two weeks of development - ...