Prenatal diagnosis of conjoined twins in the first trimester of pregnancy. A case report

Conjoined twins are an uncommon obstetric event with extremely poor prognosis in almost all cases. We report a case of monochorial monoamniotic twin pregnancy diagnosed in an ultrasonographic examination performed at 12 weeks of gestation. Both fetuses were joined at the chest and superior hemiabdomen. We show that this kind of abnormality can be diagnosed in the first trimester with a high degree of accuracy in determining the site and extent of organic attachment. Color Doppler imaging is useful for investigating the shared vascular structures. 3D ultrasound is also useful as a complement to 2D ultrasound and in parental counseling. Prenatal diagnosis in early pregnancy allows decisions to be taken early, minimizing the sequels for the pregnant woman. (C) 2009 Elsevier Espana, S.L. All rights reserved.