The incredible case was revealed after the woman, identified only as T.M., named her current boyfriend as the father of her twins.
But T.M. admitted before maternity papers were signed that she had actually slept with a different man a week after she believed she conceived with her boyfriend.
A paternity test was carried out and it was revealed that the two men had each fathered one of the twins, who are now toddlers. Paternity tests showed the woman’s former boyfriend was almost certainly the father of one twin – but wasn’t the father of the other.
It seems medically impossible, but a woman can give birth to twins with two fathers when she has sex with two different men in the same week.
In a process known as heteropaternal superfecundation, the rare incident occurs when a woman releases two eggs during her menstrual cycle and different men fertilise one egg each. It is a more common occurrence when the same dad fertilises two eggs during separate incidences of sex.
Amazingly, it is also possible for a woman to give birth to twins who have been conceived weeks or even months apart, if she continues to ovulate even after she has become pregnant, in a process called superfetation.
It is claimed that superfetation is common in some species of animals, but is extremely rare in humans.