About 12% of pregnancies begin as multiples, but fewer than 2% reach full term. Vanishing Twin Syndrome occurs when one ...

What's the meaning of fraternal twins? Fraternal twins come from two separate fertilized eggs that develop in the womb at the same time, each with their own placenta and amniotic sac. Like any ...

Identical twins are not as identical as previously assumed, according to a study published today (January 7) in Nature Genetics. Rather than having exactly the same DNA sequences, twins start ...

One twin may have a particular medical condition, while the other does not. Here again, epigenetic influences and developmental factors in the mother’s womb may influence one twin but not the other.

Researchers analyzed Norwegian information on nearly 730,000 Norwegians, including 13,800 twins, born between 1967 and 1978. After controlling for birth weight, maternal education, and other factors, ...