Related Experiment Video
Updated: Aug 17, 2026
Generation of the Early-Gestational Maternal Immune Activation Mouse Model to Assess Prenatal Inflammation on Neurodevelopment
Published on: March 24, 2026
Weight adjustment of serum markers in early first-trimester prenatal screening for Down syndrome
Tina Sørensen1, Severin Olesen Larsen, Michael Christiansen
1Department of Clinical Biochemistry, Statens Serum Institute, Denmark. TLI@SSI.dk
Objective:
To assess whether existing weight correction formulas for PAPP-A and free-beta-hCG developed for weeks 11 to 14 can be applied to pregnancies in weeks 8 to 10.
Methods:
Development of formulas based on limited data sets of 8- to 10-week pregnancies and comparison with existing formulas. Calculation of median MoMs adjusted with different formulas for weight correction.
Results:
Weight correction formulas for the gestational age of 11 to 14 weeks were not appropriate in the 8- to 10-week gestational age interval for PAPP-A, whereas existing weight correction formulas could be applied to free-beta-hCG, independent of gestational age interval.
Conclusion:
If PAPP-A is used in different gestational age intervals, weight corrections should be developed for the interval.