Scientists are exploring ways to mimic the origins of human life without two fundamental components: sperm and egg. They are coaxing clusters of stem cells – programmable cells that can transform into ...

The majority of fertilized eggs die and are resorbed into the body. ZEISS Microscopy/Flickr, CC BY-SA As an evolutionary biologist whose career has focused on how embryos develop in a wide variety of ...

Frozen embryos are filling storage banks around the world. It's a struggle to know what to do with them. Lisa Holligan already had two children when she decided to try for another baby. Her first two ...