A woman has given birth to a 'pregnant' baby. Here's how that's even possible.

Mónica Vega of Barranquilla, Colombia, gave birth this week to a baby girl at 37 weeks gestation via Caesarean section – but this was no standard delivery, according to Mamas Latinas.

The website explained that the newborn girl, Itzmara, was born “pregnant” with her own twin, and needed emergency surgery to remove the twin as soon as she was born. The parasitic twin was in its own amniotic fluid, and had an umbilical cord, bones, arms, and legs, but no brain or beating heart.

Fetus in fetu, en Colombia.
Ojalá, todo salga bien.???? pic.twitter.com/whtsnEC7yd

— ????Ri (@ARi__uy) March 19, 2019

The scenario was possible because of a condition called foetus in foetu, when one foetus becomes trapped inside its twin, making the inner twin a parasite. Foetus in foetu is extremely rare, and occurs approximately in one in every 500,000 births. There are believed to be less than 100 documented cases.

Because the condition happens early in the pregnancy, Mónica’s obstetrician Dr. Miguel Parra from La Merced Hospital was able to diagnose Itzmara’s condition, via an ultrasound which detected two umbilical cords – one being connected to the mum, and one connecting Itzmara to a mass that was growing inside of her.

The decision was made to operate on Mónica, at 37 weeks, so the foetus inside Itzmara wouldn’t continue to grow, potentially causing damage to her internal organs.

According to reports, both Mónica and Itzmara are now doing well.

However, not all cases end so positively. In 2015, a baby was born “pregnant” with twins in Hong Kong, but the condition wasn’t discovered until after the delivery. Until that point, doctors suspected the infant had a tumour, and only discovered during surgery that there were two foetuses between her kidney and her liver.

Listen to the full episode of Mamamia’s latest parenting podcast, The Baby Bubble.

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