The following references illustrate the fact that a new human embryo, the starting point for a human life, comes into existence with the formation of the one-celled zygote: "Development of the embryo ...

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 ...

The majority of fertilized eggs die and are resorbed into the body. ZEISS Microscopy/Flickr, CC BY-SA As an evolutionary biologist whose career has focused on how embryos develop in a wide variety of ...

Human bodies have to be built from a single egg cell that's fertilized by a sperm cell. Many rounds of cell division occur as the body is developing, and it seems that there are plenty of chances for ...

Infertility is a challenge that many couples face and it can affect both men and women. There are various reasons for infertility, such as hormonal imbalances, low sperm count, blocked fallopian tubes ...