“It all adds up to many rarities happening in the same cycle,”
A Chinese man learned that only one of the twins his adulterous wife gave birth to is his biological son – in response he decided that he would only raise the child that, biologically, belongs to him.
According to local outlet the Strait Herald, the man, whose name was withheld, became suspicious when one of his two sons didn’t look like him.
But the truth didn’t get revealed until the couple went to register the birth of their twins at a local police station, which in China requires couples to produce results of a paternity test to prove the babies are theirs.
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When the DNA results came back, results from the Fujian Zhengtai Forensic Identification Centre revealed one of the twins was not biologically related to the man.
The furious husband confronted his wife about the results, who denied having an affair. Instead, she argued that her husband had fabricated the DNA test results.
Eventually, the wife admitted to having slept with another man during a one-night stand.
The father said he would only be willing to raise his own son.
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According to experts, twins being born to different fathers is extremely rare among humans (but much more common among cats, cows and dogs). But, as reproductive science expert Michael Carroll explained to the Guardian, it does happen. “It all adds up to many rarities happening in the same cycle,” he said.
Another expert, Jason Kasraie of the Association of Clinical Embryologists, said there are two possible ways it can happen during sex. The first happens when a woman releases two eggs at the same time. Since sperm can survive for days in the womb and fallopian tube, a woman could have sex with one man prior to the egg being released. Just after ovulation, she would be impregnated again by having sex with a different man.
The second method? That happens when a woman releases two eggs within the same reproductive cycle, but a few days apart.
The phenomenon, known as Heteropaternal superfecundation, has a rate of between one and 400 and one in 13,000 pairs.
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