Twinning and birth defects: Rachipegal heteropagal twins and acardiac twins

Abstract

Twin pregnancies are associated with multiple birth defects. The increase in twinning was attributed to fertility treatments. Twins were supposed to be associated with increased risk of congenital malformations. Among the twins, monozygotic twins were associated with more malformations then dizygotic twins. Heteropagus conjoined twins are asymmetrical conjoined twins where one twin is normal and the other is anatomically incomplete and grossly defective, attached externally, with or without internal connection. Heteropagal Conjoined twins were classified based on the site of their union, and when the fusion occurs at the level of the spine it is called Rachipagal heteropagal twin. One of the most important complication of Monochorionic placenta is Twin to twin transfusion syndrome. The major major defect is in recipient twin there was lack of well developed cardiac structure, and the blood supply was maintained through placental vascular anastomosis with normal twin. This sequence was described as the twin reversed arterial perfusion ,also known as Acardiac Twinning. Here we are going to present two rare cases of Rachipegal Heteropagal twin and Acardiac twin.

Keywords

• acardiac twin
• congenital malformations
• rachipegal heteropagal twin
• trap sequence
• twin pregnancy