Twins found with different fathers in Vietnam

Twins, born of the same mother, but different fathers. How possible is that? Well, it is possible and it's due to a rare condition called superfecundation.

Superfecundation occurs when a woman has sex with different men within a short period of time, and fertilisation occurs. 

According to Dr. Keith Eddleman, who spoke to CNN, a man's sperm can last for up to ten days while a woman's egg has a life span of 12 to 48 hours, so there's approximately a week's time for potential overlap.

A set of twins in Vietnam are reportedly one of the ten cases reported around the world of bi-paternal twins; twins that share a mother but have different fathers.

The twins, who are now two-years-old, were reportedly taken for paternity testing after relatives enquired why the two looked so different, MSN reported.

Amongst the differences is the hair. The one child reportedly has curly hair, while the other has straight hair.

The test was done at Genetic Association of Vietnam.

They were born in northern Hoa Binh Province and are reportedly the first bi-paternal twins born in Vietnam.

Le Dinh Luong, president of the Genetic Association of Vietnam, told reporters no further information can be given about the family, due to a confidentiality agreement with the parents.