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.

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 ...

Using a tiny, spherical glass lens sandwiched between two brass plates, the 17th-century Dutch microscopist Antonie van Leeuwenhoek was the first to officially describe red blood cells and sperm cells ...

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) ...