Prediction of preeclampsia

FMF method of screening

The FMF approach to screening for PE is to use Bayes theorem to combine the a priori risk from maternal characteristics and medical history with the results of various combinations of biophysical and biochemical measurements made at different times during pregnancy.

This approach assumes that if the pregnancy was to continue indefinitely all women would develop PE and whether they do so or not before a specified gestational age depends on competition between delivery before or after development of PE.

The effects of variables from maternal characteristics and history and biomarkers is to modify the mean of the distribution of gestational age at delivery with PE so that:

In low-risk pregnancies the gestational age distribution is shifted to the right with the implication that in most pregnancies delivery will actually occur before development of PE.

In high-risk pregnancies the distribution is shifted to the left and the smaller the mean gestational age the higher is the risk for PE.

Wright D, Akolekar R, Syngelaki A, Poon LC, Nicolaides KH. A competing risks model in early screening for preeclampsia. Fetal Diagn Ther 2012; 32: 171-8.