Fraternal or dizygotic twins develop from two different eggs fertilized by separate sperm; they generally share about 50 percent of their genes. Therefore, fraternal twins are essentially like typical ...

Twins occur in about one out of 90 human pregnancies in the US. As a rule, at conception, one sperm fertilizes a single egg to produce a zygote. Two thirds of twins are fraternal, with fertilization ...

It was my third pregnancy, and when my bump grew faster, I assumed it was because I had done this before. It turned out I was pregnant with twins. They refused to take a DNA test now as adults to find ...