Sirenomelia: a rare case of foetal congenital anomaly.

Sirenomelia, alternatively known as 'mermaid syndrome' is a very rare congenital deformity in which the legs are fused together, giving them the appearance of the tail of a mermaid'. Other birth defects are always associated with sirenomelia, most commonly abnormalities of the kidneys, large intestines, and genitalia. The present case is a one of sirenomelia associated with an absent right kidney, mild left hydronephrosis, single umbilical artery, and severe oligohydramnios. We discuss the findings, relative to the present literature and related etiopathogenesis.