New Delhi: In one of the million cases, a 19-year-old woman from Brazil gave birth to twins but with two different biological fathers.
Although, this event is astounding and hard to believe this bizarre possibility lies in the biological phenomenon called heteropaternal superfecundation, in which the second ova released during the menstrual cycle is fertilized by sperm cells of another man in different sexual intercourse.
After fertilization, the babies share the mother's genetic material, but they grow in different placentas.
This phenomenon was initially presented by Archer in 1810. "Although rare in humans, heteropaternal superfecundation is common in dogs, cats and cows," a report by The Guardian says.
The woman gave birth to twins, nine months after engaging in sexual intercourse with two men on the same day. She decided to opt for a paternity test to validate her suspicions as their first birthday approached since she started to question their father.
The woman considered one man to be the father, so she gathered his DNA. However, only one child's DNA was matched.
While talking with Globo the mother said, "I remembered that I had sex with another man and called him to take the test, which was positive."
"I was surprised by the results. I didn't know this could happen. They are very similar," she further added.
The woman's physician Dr Tulio Franco said it is feasible for this to occur when two eggs from the same mother are fertilized by different males. The doctor added that the kids have the same genetic structure as their mothers.
He said that he never anticipated seeing a circumstance like this in his lifetime, in which there are only 20 other occurrences in the world.
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