Sirenomelia in twin pregnancy: A case report

Sirenomelia also known as mermaid syndrome since Greco-Roman period, is a lethal disorder characterized by a single lower extremity, with concomitant presence of several anomalies of urogenital and gastrointestinal system. Sirenomelia is a syndrome of merging, malrotation and dysgenesis of lower extremity. Merging is more correct term to use because fusion refers to joining of two processes after breakdown of intervening epithelia. Here, we present a case of dichorionic diamniotic twin pregnancy, where one foetus was diagnosed with sirenomelia associated with hemivertebra and absent right radius and ulna and the co-twin was apparently healthy.