SkyNewsNepal

Scientists in Vietnam have confirmed a case of bi-paternal twins, or twins who have different fathers. The tests showed there was no mix-up in the hospital: The twins have the same mother, but different fathers. Twins who have different fathers are extremely rare, Luong said, adding this is the first case in Vietnam that he knows of. A woman’s egg has a life span of 12 to 48 hours, and a sperm is viable for seven to 10 days, so there’s about a week’s time for potential overlap and the fertilization of two eggs by two sperm from separate acts of sexual intercourse.