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A baby was born via emergency C-section, only to be forced to undergo its own caesarean just a day later.

Performing the procedure on a newborn sounds like something out of a movie. However, it’s the result of a rare pregnancy condition that a recent case study has revealed can sometimes plague people into their adult years.

Back in March, Columbian woman Mónica Vega was seven months pregnant when an ultrasound revealed she had two umbilical cords inside her.

But, unfortunately, Ms Vega wouldn’t be giving birth to twins. Instead, tests revealed her baby girl Itzmara had absorbed the other foetus in the womb, which had then attached to her via an umbilical cord, Mamás Latinas reported at the time.

Known as foetus in fetu, the condition occurs when a deformed foetus is absorbed by its sibling and becomes a parasitic twin.

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After Ms Vega’s doctors discovered the second foetus she underwent an emergency C-section to prevent the mass from growing further and damaging Itzmara’s internal organs.

At just 24 hours old, Itzmara underwent a caesarean to remove her parasitic twin, which had no hope of surviving as there was no heart or brain.

Ms Vega’s case is extremely rare, with foetus in fetu occurring only in one of every 500,000 births and just 200 reported cases, according to a 2010 report from the National Institutes of Health.

However, not all cases of foetus in fetu are detected before birth.

In an August case report by the British Medical Journal, a 17-year-old Indian girl sought medical help over a stomach lump she’d had for the past five years that was increasing in size.

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After the girl complained of abdominal pain and was unable to eat large meals, tests revealed the lump contained “multiple teeth” and “hairs, mature bones and other body parts” from the teen’s parasitic twin she had absorbed in the womb.

Doctors successfully removed the mass, which measured more than 30 centimetres in length and 16 centimetres in width, and the patient made a full recovery.

“I was much worried about my abdominal lump. After operation I am feeling very well and my abdomen is now flat and my parents are also very happy,” the teenager, who has not been named, told the BMJ. “Thanks to all operating doctors.”

Most reported adult cases of foetus in fetu occur in men, with a parasitic twin discovered inside a 47-year-old male in 1992.