First trimester nuchal translucency: effective routine screening for Down's syndrome

The objective was to evaluate the effectiveness of 10-14 week nuchal transl ucency measurement in routine ultrasound screening for Down's syndrome. 11 398 women were scanned at 10-14 weeks of pregnancy for nuchal translucency measurements. The mean maternal age of the screened population was nut sign ificantly different from that of the booking population. A 5% screen positi ve rate was achieved by using a nuchal translucency-derived risk of greater than or equal to 1:200. Screening using this nuchal translucency risk woul d enable the first trimester detection of 16 out of 21 (76%) fetuses with D own's syndrome and 40 out of 49 (81%) aneuploid fetuses. In conclusion, thi s study demonstrates that first trimester nuchal translucency measurement i s an effective method of screening for fetal chromosomal abnormality.