Cheating on your husband and getting pregnant from it is bad enough as it is. But imagine your husband's child sharing a womb with that of your lover for nine months.

To much disbelief, a woman in Xiamen City, China, has reportedly given birth to twins from separate fathers. Chinese news site Strait Herald was told about the occurrence by Ms Zhang, who is the director of the Fujian Zhengtai Forensic Identification Centre, the government agency which ran the paternity test for the twins.

The woman’s husband, identified by Chinese media by the pseudonym Xiaolong, noticed the twins looked very different at birth. Xiaolong was particularly thrown off by the fact that one twin resembled him a lot, and one not at all. In light of this, he requested a DNA test, and when the results came out, the woman had no choice but to admit she had a one-night stand.

The story became known to the public when the couple went to register the birth of the twins at a local police station. To complete the registration, a paternity test was requested as proof the children was theirs, revealing the results.

Ms Zhang said the husband was enraged at his wife when he found out that he's only the baby daddy for one of the twins. She also said that before admitting to her mistake, the woman tried to cover up her actions by accusing her husband of falsifying the test results.

The father will reportedly raise his own child, but not the one from the other man.

The extremely rare birth of twins with different fathers is known as heteropaternal superfecundation. It can happen either if a woman has sex with two separate partners in an extremely short timespan, or if a woman releases two eggs a few days apart in the same reproductive cycle, and then has sex with different partners, the Guardian reports.

Heteropaternal superfecundation is so rare that a person is more likely to win the lottery than having twins born to different fathers, Tai Hai Net reports.