Dr.can i know . NT scan was done at 11 weeks 3 days and NT Result is 0.50mm CRL 40.4mm. (4.04cm) are these results normal ? Any risk have down syndrome baby?

Yes, these results are normal. An NT of 0.5 mm at a CRL of 40 mm is well below the 3 mm cut-off, so the scan shows a low risk of Down syndrome. A normal NT lowers the risk but does not exclude it, and a blood test combined with the scan gives a more accurate figure. Discuss the report with your doctor.