A new study takes a tour of the history of research into human embryology and development to show the "cycles of attention" that led to major scientific breakthroughs. Analyzing the past sheds light ...

The first steps of human development—those that occur within the first few weeks of pregnancy—remain mysterious in many ways. Within a week of fertilization, human embryos form a blastocyst, which ...

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 ...

Single-embryo transfer has been recommended to reduce the incidence of multiple gestations when in vitro fertilization is performed in women under 36 years of age. We designed a prospective, ...