The significance of choroid plexus cysts, echogenic heart foci and renal pyelectasis in the first trimester

Objective To determine the significance of certain soft ultrasonographic ma rkers for chromosomal abnormalities in the first trimester. Design This was a prospective cross-sectional study. Setting University Department of Obstetrics and Gynaecology, London, UK. Methods A total of 5385 women from an unselected population underwent a det ailed assessment of fetal anatomy at 11-14 weeks of gestation (confirmed by crown-rump length) by transabdominal sonography (5.0 MHz) and transvaginal sonography (6.0 MHz,) when necessary. Results In normal fetuses, the prevalences of choroid plexus cysts, pyelect asis and echogenic heart foci were 2.2, 0.9 and 0.6%, respectively in the f irst trimester and 2.0, 0.8 and 0.8%, respectively in the second trimester. Pyelectasis (likelihood ratio = 8.0, p = 0.03) and echogenic heart foci (l ikelihood ratio = 10.3, p = 0.02) were found to be associated significantly with fetal aneuploidy, while choroid plexus cysts were not. Conclusions Although the majority of aneuploidies were detected by increase d nuchal translucency and/or the presence of structural abnormalities (78%; 25/32), the use of soft ultrasonographic markers in the first trimester wo uld have increased the overall detection by a further 3%. These data are pr eliminary and many thousands of pregnancies will need to be examined to det ermine the significance of the individual markers in different chromosomal abnormalities.