Related Experiment Video
Updated: May 12, 2026
Semiconductor Sequencing for Preimplantation Genetic Testing for Aneuploidy
Published on: August 25, 2019
Maternal serum placental growth factor and α-fetoprotein testing in first trimester screening for Down syndrome
Kim Donalson1, Steve Turner, Lesley Morrison
1Biochemistry Department, Royal Victoria Infirmary, Newcastle, UK. kim.donalson@nuth.nhs.uk
Objective:
The aim of this research was to evaluate the addition of first trimester maternal serum placental growth factor (PlGF) and α-fetoprotein (AFP) to the combined test for Down syndrome and a serum only protocol of PlGF, AFP, free β-human chorionic gonadotropin and pregnancy-associated plasma protein-A.
Methods:
Samples were from 92 Down syndrome cases with 552 matched controls. All women had a combined test at 11-14 weeks gestation. PlGF and AFP were measured and expressed in multiples of the gestation-specific median (MoM), adjusting for maternal weight and smoking status. Multivariate Gaussian modeling was used to predict detection and false-positive rates.
Results:
The median PlGF level in the cases was 0.694 MoM and controls 1.000 MoM (p = <0.0001). The corresponding values for AFP were 0.764 MoM and 0.990 MoM (p < 0.0001). Statistical modeling predicted that for a given false-positive rate, the addition of PlGF to the combined test increases the detection rate by 4-7%. For a given detection rate, the false-positive rate could be almost halved. When both PlGF and AFP are used, the detection rate increase is 5-8%. A serum only protocol had a predicted a detection rate of 71% for a false-positive rate of 5%.
Conclusions:
Results suggest a substantial benefit of adding PlGF to the combined test.
