Mono-mono twins are an incredibly rare type of identical twins who share both a placenta and an amniotic sac. While this makes for a high-risk pregnancy, advances in monitoring and treatment have ...

New reproductive technologies have yielded a vast array of novel variations on the two conventional twin types—identical and fraternal—as well as some curious twin-like sibships. When a Canadian ...

New reproductive technologies have yielded a vast array of novel variations on the two conventional twin types—identical and fraternal—as well as some curious twin-like sibships. When a Canadian ...

When Gabrielle Taylor shared a TikTok about how her identical twins were labeled “Twin A” and “Twin B” before birth, she ...

The Science of Siblings is a new series exploring the ways our siblings can influence us, from our money and our mental health all the way down to our very molecules. We'll be sharing these stories ...

Despite looking very much alike, no two people are exactly the same; not even identical twins. And I don’t mean the fact that they have different personalities. They often differ in regards to their ...

Back when they were single, identical twin sisters Venessa and Kerissa Sealby never dreamed they would marry identical twin brothers. “We didn’t have any interest in dating twins,” Venessa, 28, tells ...