Conjoined Twin: Review with a Case Report

Abstract

Conjoined twins are suggested to result from aberrant embryogenesis. The two main theories proposed
to explain the phenomena are fission and fusion. The incidence rate is 1 in 50,000 births; however, since
about 60% of the cases are stillborn, the true incidence is approximated at 1 in 200,000. There is a higher
predisposition towards female than male gender with a ratio of 3:1. Conjoined twins are classified based
upon the site of attachment. The extent of organ sharing, especially the heart, determines the possibility and
prognosis of a separation procedure. Meticulous preoperative evaluation, planning, and preparedness of the
team are crucial for a successful separation. Separation of conjoined twins poses several technical, legal,
and ethical issues. With the aid of diagnostic imaging techniques, such as ultrasonography (US) and threedimensional
magnetic resonance imaging (3D-MRI), physicians are able to make prenatal diagnoses.