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 ...

Medical professionals and fertility clinics are prohibited, under penalty of law, from experimenting on a prospective parent(s) human reproductive material, including sperm, ovum, or embryo at any ...

Who hasn't seen it before: the view through the microscope in which a sperm penetrates an egg cell and fertilizes it. This fundamental step in procreation happens dynamically and seemingly without ...

Roughly 50 years ago, scientists pursued a line of inquiry about the creation and development of human embryos in the lab. As of now, the extent of this research is limited to the first 14 days ...