A teen's abdominal pains turned out to be a fetal twin

Cropped close up view girl touch stomach suffers from severe ache sitting on sofa, twinges of pain caused by menstrual period, gastric ulcer, appendicitis or disease of gastrointestinal system concept
A teen's abdominal pain turned out to be a fetal twin. (Photo Getty Images)

In the best-case medical scenario, you go to a doctor and learn that the fears about your mysterious symptoms are unfounded. But in a worst-case scenario, you might have a medical condition you didn't even know existed. If you're squeamish, you might want to stop reading, because this rare story isn't for the faint of heart. A 17-year-old in India had an abdominal mass removed that turned out to be the remains of a fetal twin.

As Gizmodo and other outlets have reported, the unnamed teen had experienced abdominal pain for years. When she visited a doctor about the growing lump in her abdomen, medical experts found that the tumor in question was, in fact, a case of fetus in fetu.

"The contents of the tumour consisted of hairs, mature bones, and other body parts," the BMJ case report, written last month, about the medical rarity explains. It turned out that the mass had been growing inside her for as long as she'd been alive—it even had teeth.

Fetus in fetu involves a fetal twin that's essentially been absorbed into the other twin's body. The new case is especially rare because, as the BMJ points out, other instances have been "usually detected in early age and in male gender." The journal noted that there have been less than 200 cases of fetus in fetu ever recorded, with only seven of those observed in patients 15 or older.

Fortunately, in this case, the teen's doctors were able to remove the mass, and she is making a healthy recovery. According to the BMJ report, "her postoperative period was uneventful," and doctors have ben monitoring her for two years. (Still, the photos of the tumor are pretty gruesome.)

"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 teen said in the BMJ report. "Thanks to all operating doctors."

Everything worked out for this teen in the end, and it sounds like she's in good health. But the slightly terrifying story is a good reminder to schedule that doctor's visit you've been putting off, just in case.

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