A Case of Retroperitoneal Mass in Infancy, Fetus in Fetus / 대한산부인과학회잡지

ABSTRACT

"Fetus in fetus" is a rare pathologic feature consisting of a parasitic twin included within the body of the other twin, which most likely arises from inclusion of a monozygotic, diamniotic twin pregnancy. The exact embryogenesis of fetus in fetus is controversial. Some investigators propose that it is a highly organized teratoma. Since the condition was first described by Meckel in the late 18th centry, approximately 100 cases have been reported in the literature. Most cases present as an abdominal mass during the first year of life, with a few cases being detected prenatally by ultrasound examination. So we report one case of fetus in fetus detected by ultrasound examination prenatally.