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In China, doctors surgically removed the fetus of a twin from the head of its one-year-old sister, who had developed upper limbs, bones, and fingernails a condition known medically as fetus-in-fetu.
Doctors have also stated that this fetus has most likely been growing inside the womb with its sibling for months. And it has the potential to expand further.
It is a medical rarity that has been encountered by doctors all over the world.
The four-inch-long fetus was discovered when the parents took their daughter to the doctor for neurological issues and an enlarged head.
The fetus was recorded in December in the journal Neurology of the American Academy of Neurology which noted that a girl was brought to the hospital for abnormalities in her motor skills and problems with walking and sitting.
The doctors from the hospital did not provide further details regarding this condition. The CT scans have revealed her sibling that was seen pressed with the girl’s brain.
According to the available details, the girl also had a fluid inside her brain which resulted in her head’s enlargement, with a possibility of causing seizures and extreme sleepiness.
The fetus survived due to the blood supply shared with the host. The long-term complications for the girl cannot be foretold at this point, the details show.
Dr. Zongze Li, a neurologist at Huashan Hospital who treated this abnormality believed “this condition is caused by unseparated blastocysts.”
“The conjoined parts develop into the forebrain of the host foetus and envelop the other embryo during neural plate folding,” he added.
This is the 18th reported case of its kind. In 2017, Thai doctors discovered three siblings inside the skull of an unborn baby with fully developed organs such as the nervous, digestive, and respiratory systems.
The foetus was linked by a single artery and vein, dubbed “the umbilical cord” by doctors.
In 2015, doctors in China discovered an unborn fetus inside the scrotal sac of its male twin.
The foetus was also surgically removed from the host, and the host recovered completely.
Furthermore, the foetus was found in other parts of the host’s body, including the pelvis, mouth, and intestines. There have been 200 cases reported, with 18 of them developing inside the skull.
Doctors are currently unable to determine how this condition occurs; however, it is known that it is caused by the incomplete separation of one egg. According to some experts, “it occurs as a result of late cell division.”
