A woman in New Jersey was only filing for child support when she claimed that a man fathered her twins. Little did she know that her request would take a bizarre turn.

The State Superior Court in Passaic Country, through Judge Sohail Mohammed, ruled that the man, identified as A.S. in court documents, will only be responsible for providing child support to one of the twins. According to the ruling, A.S. is only father to one of the twins. The other, it turns out, was conceived when the woman had sexual relations with another man during the same week that she had sex with A.S., believed to be the time that resulted in the twins' conception.

Twins having different fathers? It sounds impossible but it's not. It's what is called as superfecundation. Karl-Hans Wurzinger, laboratory director for Laboratory Corporation of America's Identity Testing Division, testified in court that one out of 13,000 paternity cases involving twins results in identifying different fathers. The case is illustrated classically in medical textbooks as black and white babies being born as twins.

A sperm can be useful for up to five days after intercourse. As such, if the twins' mother had sex with one man and ovulated, and then had sex with another man, all within a week's time, it is possible for one man's sperm to fertilize one egg and another's sperm to fertilize another egg.

The phenomenon is still rare but its starting to become more common in light of assisted reproductive techniques, such as when gay couples both contributing sperm to a pregnancy.

The twins A.M. And B.M. were born in January 2013. Their mother, T.M., filed for child support, which the Passaic County board of social services forwarded on her behalf. A paternity test was done to facilitate the petition but when the results came out, it showed that A.S. is only responsible for one of the twins. It was in a testimony that it was revealed the mother had sex with another man during the same week she was with A.S.

The identity of the other man, the second father, has not been established, but as A.S. has been identified as indeed a father to at least one of the twins, he was ordered to pay $28 a week in child support.

Across the United States, only a handful of cases of superfecundation have been reported.

Donnie Ray Jones | Flickr