Doctors at Vietnam's Hue Central Hospital have removed a partially formed fetus from the stomach of a two-month-old baby during a two-hour surgery on Sep. 12.
The infant is in stable condition after the surgery, Pham Nhu Hiep, the hospital vice director, said.
The "extremely rare" case is known as fetus-in-fetu, in which one twin is absorbed inside the body of another, said Nguyen Thanh Xuan, one of the surgeons who operated on the baby.
Fetus-in-fetu occurs in about one of every 500,000 live births, according to a report in a June 2000 issue of the US journal Pediatrics.
Doctors at the Hue Central Hospital remove a 1-kg fetus from a boy's stomach on September 12, 2014. Photo credit: the Hue Central Hospital
The boy comes from the central province of Quang Ngai, roughly 230 kilometers from Hue City.
He had been taken to Hue Central Hospital by his parents, who were concerned of his swollen belly, said the hospital vice director Hiep.
Initial tests suggested the infant had a giant tumor in his stomach.
However, during the surgery doctors discovered a twin in the boy's stomach, complete with legs, arms, spinal column, part of the liver, and intestine. The fetus weighed 1kg, doctors said.
A fetus-in-fetu can be considered alive, but only in the sense that its component tissues have not yet died or been eliminated. All cases of fetus-in-fetu present critical defects, such as no functional brain, heart, lungs, gastrointestinal tract or urinary tract, according to a 2008 study by Egypt’s Assiut University.
While a fetus-in-fetu can share select morphological features with a normal fetus, it has no prospect of any life outside of the host twin. Moreover, it poses clear threats to the life of the host twin on whom its own life depends, the study said.