Lab-grown structures with the potential to develop into fetuses should be defined — and regulated — as embryos, some researchers say. It is time for a redefinition of the human embryo, a team of ...

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 ...

With embryolike constructs built entirely from stem cells, researchers can revolutionize our understanding of development. But how close to an embryo is too close? In April, researchers in China ...

cases and I.V.F. disputes, the frozen embryos vials like these will hold are increasingly caught The Embryo Question is a three-part series about the cluster of cells at the crossroads of science, ...