Fetal nuchal translucency: ultrasound screening for chromosomal defects in first trimester of pregnancy.
British Medical Journal 1992; 304 doi: https://doi.org/10.1136/bmj.304.6831.867 (Published 04 April 1992) Cite this as: British Medical Journal 1992;304:867- K. H. Nicolaides,
- G. Azar,
- D. Byrne,
- C. Mansur,
- K. Marks
- Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London.
Abstract
OBJECTIVE--To examine the significance of fetal nuchal translucency at 10-14 weeks' gestation in the prediction of abnormal fetal karyotype. DESIGN--Prospective screening study. SETTING--The Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London. SUBJECTS--827 fetuses undergoing first trimester karyotyping by amniocentesis or chorionic villus sampling. MAIN OUTCOME MEASURE--Incidence of chromosomal defects. RESULTS--The incidence of chromosomal defects was 3% (28 of 827 cases). In the 51 (6%) fetuses with nuchal translucency 3-8 mm thick the incidence of chromosomal defects was 35% (18 cases). In contrast, only 10 of the remaining 776 (1%) fetuses were chromosomally abnormal. CONCLUSION--Fetal nuchal translucency > or = 3 mm is a useful first trimester marker for fetal chromosomal abnormalities.