Sperm have to wiggle vigorously to reach an egg, and that motion is key to a clever new fertility test. The technique, tested with bull semen and detailed in Advanced Materials Interfaces, harnesses ...

Ultrastructure expansion microscopy of murine male germ cells reveals the fine molecular structures of centrioles (shown in the enlarged image). DNA is stained in blue, and the chromosome axis in red.

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 ...