A prospective cohort study on association of first-trimester serum biomarkers and risk of isolated foetal congenital heart defects.

BACKGROUND: This study aims to assess the association between first-trimester biomarkers in foetuses with a non-chromosomal congenital heart defect (CHD) and compares it to the matched healthy foetuses. METHOD: Nuchal Translucency (NT), Pregnancy-Associated Plasma Protein-A (PAPP-A) and free beta-human Chorionic Gonadotropin (ß-hCG) were evaluated in 56 isolated foetal heart defects and 224 controls. The CHDs were further divided into Critical CHD (C-CHD) and Non-critical CHD (N-CHD) groups. RESULTS: The multiple of the median (MoM) values for PAPP-A were significantly lower (0.87 MoM vs. 0.92 MoM; p = 0.008) in the total CHD group than in controls. The median of foetal NT values was significantly higher in the total CHDs than in controls (1.16 MoM vs. 1.03 MoM; p < 0.001), especially for C-CHDs (1.28 MoM; P < 0.001). There were no significant differences in terms of PAPP-A (p = 0.779) and foetal NT values (p = 0.760) between the N-CHDs and control groups. There were no significant differences within the groups based on free ß-hCG, except for a lower ß-hCG in C-CHD group than in the control group (0.95 MoM vs. 1.11 MoM; p = 0.022). CONCLUSION: Lower PAPP-A levels and increased NT thickness were associated with an increased risk of CHDs, especially the critical type of CHDs.Clinical significanceMaternal serum PAPP-A, measured in the first trimester, is significantly lower in CHD.Foetal NT is significantly thicker in foetuses with CHD, especially those with critical CHD.Maternal serum ß-hCG was only decreased among critical CHD group.