News

With each week of pregnancy, your baby-to-be is developing in leaps and bounds. In the early stages, they are called a zygote. They then progress to an embryo, fetus, and finally, baby. You might ...
Four teams have coaxed human stem cells to organize themselves into embryo-like forms. The advance could shed light on fertility. By Carl Zimmer In its first week, a fertilized human egg develops ...