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 ...

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 ...

A pregnancy test detects the presence of the pregnancy hormone human chorionic gonadotropin, or hCG, in a person’s body. But the body doesn’t produce that hormone until several days after conception.

New Haven, Conn. — 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 ...

PIERRE, S.D. (KELO) — The South Dakota Constitution could soon include a new section that would define human life as including the unborn, during the embryonic and fetal ages of fertilization to full ...