Question
The risk ratio for Down syndrome is 1 in 408, with a cutoff risk ratio of 1 in 200; the risk ratio for open neural tube defects is 1 in 1282, with a cutoff risk ratio of 1 in 270. How should these data be interpreted?
Answer
Based on the provided data, the risk ratio for Down syndrome is 1 in 408, with the cutoff risk ratio at 1 in 200; the risk ratio for open neural tube defects is 1 in 1282, with a cutoff risk ratio of 1 in 270. These results indicate that your screening results are within the normal range, but the risk ratio for Down syndrome is slightly above the cutoff value. Professional advice is that amniocentesis is not necessary. Down syndrome screening is a tool for risk assessment, not a diagnostic method, and thus it only indicates high or low risk and cannot directly determine the presence of abnormalities. Preventive measures include prenatal screening,