Department of Obstetrics and Gynecology, Ain Shams University, Cairo, Egypt.
Introduction
Conjoined twinning is a rare anomaly, occurring in 0.2:10,000 births [1], with 75% occurring in females [2]. Thoracoomphalopagus occurs most frequently, and the prognosis is generally poor [3]. Conjoined twins are derived from a single ovum and therefore have the same genetic and chromosomal constitution. We present a third trimester ultrasound diagnosis of thoracoomphalopagus twins.
Case report
A 21-year-old woman was referred to our department at 32 weeks gestation due to suspected conjoined twins. The patient was not exposed to any medications or teratogenic exposures. Her personal and family history were unremarkable. The ultrasound revealed a live, thoracoomphalopagus twin gestation without fetal gastrointestinal obstruction. Heads and extremities appeared normal. Their abdominal walls were fused with an omphalocele of one of them. The external genitalia were female. The spine of one twin was scoliotic. The liver was shared but the stomachs, kidneys and bladders were separated. An abnormal heart was shared. The fetal biometry revealed smaller head parameters (less than 2SD), and normal long bones parameters in both fetuses. The twins were considered inseparable. A Cesarian section was indicated. After delivery a severe respiratory distress developed in the scoliotic baby and at the second day the babies died due to cardiac arrest.
Image 1, 2: 32 weeks of pregnancy. Thoracoomphalopagus - fused abdomens and livers are visible.