Reviewed by Roy Benaroch on February 28, 2017


The New York Times: "Toddler Twins: Secret Language or Babble?", March of Dimes: "Being pregnant with twins, triplets and other multiples.", American Pregnancy Association: "Are My Twins Identical Or Fraternal?", HL, Lu. Journal of Forensic Science, July 1994., AudioJungle

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Video Transcript

Ready to double up on your twins knowledge? Let's get started!

First, have you ever seen those viral videos of toddler twins appearing to talk to each other in their own secret language? It's a cute theory, but they're actually just having fun babbling, mimicking sounds they heard Mom and Dad make, and building their budding speech skills.

Now, how come some twins look exactly alike and others don't? Rewind back to their earliest days in the womb. Identical twins come from one fertilized egg that splits in two. Fraternal twins come from two eggs fertilized by two different sperm.

Next, maybe you've heard twins can have different fathers. Turns out it's rare, but possible! It can happen when a woman has sex with two men a few days apart while she's ovulating.

Finally, a woman may be more likely to have twins if she's in her late 30s or obese. The odds may also rise if she had a fertility treatment or if twins run in her family.

Seeing double yet? We hope you're twice as savvy about twins now.

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