Dose dependency between cigarette consumption and reduced maternal serum PAPP‐A levels at 11–13⁺⁶ weeks of gestation

Abstract

In first-trimester screening for Down syndrome by maternal serum PAPP-A and free beta-hCG the impact of correcting for the dose dependant rather than the all or nil effect of smoking is marginal. However, a dose dependent correction improves the accuracy of the individual patient-specific risk.