Woman, 19, gives birth to twins by TWO fathers after having sex with both of them on same day
A WOMAN of 19 woman has been left 'surprised' after she gave birth to twins by two different fathers.
Medics in Portugal said this would be the twentieth known case of heteroparental superfecundation.
This can happen in two ways.
The first is if a woman has sex with two different men prior to her ovulation and the sperm are present in the fallopian tubes when two eggs are released.
It can also happen if a woman has sex with two different men after ovulating and the sperm are then able to fertilise two eggs.
The unnamed woman from southwest Goiás gave birth to twin boys.
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Doctor Túlio Franco, who had been treating the woman, said her pregnancy had 'been smooth', G1 News reported.
"The boys were born healthy and never had health problems.
"It's extremely rare. It happens one in a million. I never imagined that I would see a case like this in my life".
The mother of the twin boys exclaimed that she didn't know this could happen.
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"I was surprised by the results. I didn't know this could happen. They are very similar," she added.
While the two boys are similar, she said doubts had arisen about their paternity.
Because of this, when they were eight months old, she took paternity tests for them - with the result being positive for just one child.
It was then that she remembered she'd had sex with two men on the same day.
The mum now says one of the fathers acts as dad to both boys - and had made this official on record.
She said he takes care of them both and gives her all the support she needs.
The rare medical phenomenon is also common in other animals, like dogs, cats and cows.
It's a deliberate tactic, employed by females to increase the chances of producing multiple offspring.
But humans, who don't need to have lots of babies all at once, don't tend to do this - however it can happen.
It doesn't even need to require sex with multiple partners at the same time, or in very quick succession.
The rare event can happen if sperm survives for a few days in the female reproductive tract, and a woman produces two eggs at once.
But the odds are slim - it would mean sperm having to survive for days from both men and a double egg release in the same cycle.
Experts have previously thought that the chances could be one in 13,000 - although it's agreed that it's complete guesswork.
In September 2020, a woman in Wiltshire gave birth to twins conceived three weeks apart - although the boys have the same dad.
Gabriella Christmas, 30, was delighted to find out she was pregnant but at a five-week scan a shadow was spotted.
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But medics told her the shadow was another baby in an extremely rare case of superfetation.