Reduction in Down's syndrome screening acceptance is predominantly observed in women aged 25-35 years.

Background: The risk of having a child with Down's syndrome increases with maternal age. However, uptake of screening has never been analyzed according to age. Different studies have shown different screening uptake rates, some low and some high, but it is not clear which age categories are responsible for these trends.
Aims: To demonstrate if any age cohorts are responsible for the noted decline in uptake of serum screening.
Setting: A large teaching hospital in Hull and East Yorkshire, which has offered second trimester serum screening for Down's syndrome for over 16 years using the same test (triple test).
Main Outcome Measures: Uptake of serum screening for Down's syndrome in each 5-year age cohort per year, over 4 years. A secondary outcome measure was the uptake according to parity.
Methods: We accessed our hospital records covering a 5-year period for all women booking and delivering in a large North of England teaching hospital. The women were categorized into 5-year age cohorts for analysis of the data.
Results: Down's syndrome screening uptake rates indicate a decline from 63.2 and 65.1% in 2003 to 38.6 and 39% in 2006, respectively, in the age groups 25-29.9 and 30-34.9 years who constitute at least 50% of all pregnant women. There was no evidence of the effect of parity on serum screening.
Conclusion: It is apparent that the noted overall decline in the trends of serum screening uptake are due to the reduced uptake by the 25-35 years age group.