At just three weeks old, the girl – who was born to Chinese mainland parents – underwent successful surgery and was discharged just eight days later from the hospital, according to the Hong Kong Medical Journal.
Doctors removed the foetuses, which weighed 14.2 grammes and 9.3 grammes, respectively. Each had an umbilical cord, legs, arms, a spine, intestines, skin, and a rib cage. The report says that the foetuses were about eight to 10 weeks gestated.
According to the report, the condition – called feotus or foetu – occurs about one in every 500,000 births in the worlds and less than 200 cases have ever been reported.
“It was almost impossible to detect during the prenatal check-up, as the emrbyo inside the baby was too small,” said Dr Yu Kai-man, a specialist in obstetrics and gyneacology.
“Since it is impossible for the little girl to have conceived the pregnancy on her own, the fertilisation of the twin fetuses, of course, belongs to her parents, which has gone to the wrong place.”
Though the report says it is not exactly known how the phenomena happens, it suggests a possible link to the mother’s multiple abortions.
“The widespread use of antenatal ultrasound in early gestation may provide more concrete evidence... and shed light on this intriguing condition,” the report said.