For more than a century, scientists have debated whether intelligence is mostly a product of nature or nurture. Identical ...

It makes sense that identical twins would have the exact same DNA, right? Spoiler alert: Not always! Here's why. Identical twins (also called monozygotic or MZ twins) are conceived when a single sperm ...

After believing that her daughters were fraternal twins for so long, a mom was stunned when a genetic test revealed otherwise. Not long after Tamara Vanderent, 30, discovered that she was expecting ...

If you’re newly pregnant with twins, you may already be wondering if you’ll be welcoming two boys, two girls, or one of each into your family in a few months' time. But what about if you're having ...

The mom was 20 weeks pregnant when she discovered that her twins, Graylen and Chaysen, had twin-to-twin transfusion syndrome.