Many state legislatures are seriously considering human embryos at the earliest stages of development for legal personhood. Total abortion bans that consider humans to have full rights from the moment ...

In a common metaphor used to describe human fertilization, sperm cells are competitors racing to penetrate a passive egg. But as critics have noted, the description is also a 'fairy tale,' rooted in ...

Add Yahoo as a preferred source to see more of our stories on Google. As an evolutionary biologist whose career has focused on how embryos develop in a wide variety of species over the course of ...

Long before pregnancy begins, your body is already shaping the conditions for conception. Hormones are signalling, eggs are maturing over months, sperm are regenerating every few weeks, and your ...