Maternal Serum Screening Markers and Adverse Outcome: A New Perspective

Abstract

There have been a number of studies evaluating the association of aneuploidy serum markers with adverse pregnancy outcome. More recently, the development of potential treatments for these adverse outcomes as well as the introduction of cell-free fetal DNA (cffDNA) screening for aneuploidy necessitates a re-evaluation of the benefit of serum markers in the identification of adverse outcomes. Analysis of the literature indicates that the serum markers tend to perform better in identifying pregnancies at risk for the more severe but less frequent form of individual pregnancy complications rather than the more frequent but milder forms of the condition. As a result, studies which evaluate the association of biomarkers with a broad definition of a given condition may underestimate the ability of such markers to identify pregnancies that are destined to develop the more severe form of the condition. Consideration of general population screening using cffDNA solely must be weighed against the fact that traditional screening using serum markers enables detection of severe pregnancy complications, not detectable with cffDNA, of which many may be amenable to treatment options.

Keywords: IUGR; aneuploidy screening; fetal loss; open neural tube defects; placenta accreta; preeclampsia; preterm birth.

Figure 1

Comparison of incidence of adverse outcomes due to all causes with incidence of chromosomal abnormality. Data for incidence of adverse outcome from Lisonkova et al. [35]. Data for incidence of chromosomal abnormality from Wapner et al. [36]. NICU = Infant admitted to neonatal intensive care unit, PCS-Duplications/Deletions = Chromosome microdeletions and duplications with potential for clinical significance, T21/18/13/X/Y = trisomy 21, trisomy 18, trisomy 13 and sex chromosome abnormalities.

Figure 2

Detection Rate of IUGR using PAPP-A. The numbers indicate the associated references.