A Brazilian woman has made headlines after her infant twins tested positive to different bio-dads in a DNA test, local news outlet Globo reported.

The situation is an unusual scenario called heteropaternal superfecundation. It occurs when a second ova discharged during the same menstrual cycle is additionally fertilized by the sperm cells of a different man in a separate sexual encounter.

According to the 19-year-old mum, she gave birth to the twins nine months after sleeping with two men on the same day. She conducted the tests to ascertain the father of the kids but was surprised with the test results. 

“I remembered that I had had sex with another man and called him to take the test, which was positive,” the woman said requesting her identity to be concealed. 

“I was surprised by the results. I didn’t know this could happen. They are very identical,” she added. 

Medical practitioner Tulio Franco confirmed the possibility of the case but admitted its rareness. 

“It is possible to happen when two eggs from the same mother are fertilized by different men.

“The babies share the mother’s genetic material, but they grow in different placentas,” Mr Franco said.