A word to the wise – don’t have sex with more than one guy when you’re ovulating. You could end up with twins; each with a different daddy.

That’s what happened to one woman in north Poland. She was having sex with her husband, and having an extramarital affair on the side. She ended up giving birth to fraternal twins – a little boy and a little girl. After paternity tests were performed, it was discovered that the baby boy was fathered by her husband, and the baby girl was her lover’s child.Talk about awkward. And what’s even stranger is that the woman is now divorcing her husband, and she and her lover are taking care of the twins. (Poor hubby!)

While it’s extremely rare, having twins with two different dads is a phenomenon called “heteropaternal superfecundation.” It occurs when a woman ovulates two eggs and sleeps with two different men around the same time. According to Time Magazine, these Polish twins are  the 7th case in history of heteropaternal superfecundation.

How is Heteropaternal Superfecundation Possible?

During ovulation, which usually occurs on day 14 of a typical 28-day menstrual cycle, your ovaries release one egg. In some cases, you may release two eggs. If those eggs are fertilized, they will result in fraternal twins. (In the case of identical twins, the one fertilized egg splits into two.)

Since sperm can remain alive and viable for up to five days in a woman’s body, if she has sex with two different men within that five day time period, it’s possible for her twins to have two different fathers.

It’s possible, but extremely rare.

Want to know more?

Watch the TV report from NBC’s Today Show about this bizarre, but very interesting news story.

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Fun Facts about Fraternal Twins

* Fraternal twins usually runs in families. So if someone in your family gave birth to fraternal twins, you are a greater chance of having twins.

* Fraternal twins can be both boys or girls. They can also have different blood types.

* Some fraternal twins – like the Olsen twins – look almost identical, while others look nothing alike.

* Using fertility drugs and using IVF (in vitro fertilization) to help you get pregnant makes it more likely that you’ll have fraternal twins.

* Around 3 percent of all U.S. Births are twins.

* Fraternal twins are more common than identical twins.

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