Antenatal diagnosis of a sacrococcygeal teratoma.

Although rare, sacrococcygeal teratoma is the most common congenital tumor. We report a case of a precociously diagnosed and rapidly growing cystic lesion. These tumors may be associated with hemodynamic and hemorrhagic complications. Therefore, affected fetuses should be carefully followed during the entire pregnancy by ultrasound and MR imaging in order to evaluate the evolution of the mass, its consequences on the fetal organs and to appreciate the wellbeing of the fetus. Delivery and post natal work up can therefore be optimized.