Doctors in Mumbra, India were surprised to be confronted with a very rare case of fetus in fetu.
While the mother was pregnant, she went in for a routine scan. It was then that her doctor found an abnormal mass inside the fetal sac. Nine days after that scan, the mother gave birth. The baby was otherwise healthy, aside from a seven-centimeter mass lodged in his stomach.
It turned out that this mass was the baby's malformed twin. It had arms, legs, and even a brain, though it did not have a skull bone.
Fetus in fetu is a very rare condition. There are fewer than 200 documented cases in the entire world. The condition also occurs only in one in every 500,000 births. Scientists have put forward different theories in how this condition develops, one of which is that it the “parasite” twin starts out as a normal embryo. However, the other twin then envelops the one which will eventuallly become the “parasite”.
A parasitic twin will not be able to survive on its own, outside of its twin. It lacks the necessary development and organs in order to be able to function as a separate human being. In some cases, the parasitic twin may pose a danger to its twin's life, because it shares the same sources of nutrients. There have also been reports of grown individuals with growing abnormalities on their bodies, which turned out to be their parasitic twin.
Sometimes, the parasitic twin makes itself known during pregnancy, like in the case of the baby in Mumbra. Other times, however, it can take years before the host twin himself or herself experiences the effects of having a parasitic twin.
Another similar case of fetus in fetu occurred in Indonesia just this March. The baby was already 10 months old when his abdomen began to swell. Fearing that he had a tumor, his parents rushed him to the hospital. When doctors performed scans, they discovered that the growth was actually the baby's parasitic twin. Scans revealed that the malformed twin had a spine and limbs, but not much else.
Medical professionals anticipate that the number of parasitic twins may rise as more people undergo reproductive treatments.
Though some scientists have attempted to explain why fetus in fetu develops, others have figured that there may be no real explanation for it. "Weird things happen early, early in the pregnancy that we just don't understand," obstetrician Draion Burch tells LiveScience.
Though doctors operated on the baby in Mumbra quite soon after his birth, he is reportedly doing well. The baby boy in Indonesia also recovered from his surgery well and there were no complications. It may be that though fetus in fetu can be a dangerous and potentially painful condition, getting rid of the parasitic twin may be not be too risky.
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