For decades, scientists knew that male embryos in many mammal species—such as cows, mice, and even humans—tend to grow faster than female ones. But no one really knew why. The new study, published in ...

Scientists in Oregon have achieved something that many thought might be impossible. They said Wednesday that they have cloned human embryos and then harvested the embryo's stem cells. The discovery, ...

See more of our trusted coverage when you search. Prefer Newsweek on Google to see more of our trusted coverage when you search. What do the earliest stages of a pregnancy look like? Embryonic ...

New "squishy" lasers could help solve the mystery of the biological forces that control the development of embryos and cancerous tumors. Their innovative technique could transform our understanding of ...

Implantation, one of the most poorly understood phases of early human development, occurs in the depths of the womb, at a time when embryos are microscopic, fragile, and well out of reach. Until ...

Cornell researchers have uncovered the genetic triggers that cause male and female bovine embryos to develop differently, as early as seven to eight days after fertilization. The breakthrough in basic ...