[Early ultrasonic diagnosis of thoracopagus]

Two cases of early ultrasonic diagnosis of conjoined twins (thoracopagi) in the 13th and 21th week of pregnancy, respectively, are reported. Heart and liver were fused in both and the upper gastrointestinal tract in one of the pairs. Once an ophalocele was seen. The most important ultrasonic criteria were close and fixed position of the twins to each other, ventral fusion of the thoracal and abdominal contours and detection of joint organs. Since hearts and livers were not paired, there was no chance of any successful therapy and on the parent's request, both pregnancies were terminated.