Doctor’s TikTok video lifts the lid on how twins can have different dads

A Canadian doctor has taken to TikTok to educate users on the rare instances where sets of twins are born to different fathers.

Dr Michael Narvey, a newborn intensive care specialist from Winnipeg, Canada, addressed followers on his channel, providing a simple explanation as to how this ‘exceedingly rare event’ can happen.

An unusual occurrence

The video, which has been viewed over 15,000 times, saw Dr Michael going into detail about the rare phenomenon of superfecundation in humans.

Superfecundation, which is common in animals such as cats, dogs, and cows, can happen in two ways.  

The first is when a woman has sex with two different men prior to ovulation. Sperm is then present in the fallopian tubes when two eggs are released.

It can also happen when a woman has sex with two different men after she has ovulated, and the sperm are then able to fertilise two eggs.

Viewers of Dr Narvey’s channel were baffled by the revelation, which is commonplace among some female mammals as a way of ensuring multiple offspring.

In humans the chances of superfecundation occurring are slim. There have been fewer than 10 cases recorded worldwide, although there are likely to be more that are not known about.

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