Maternal plasma miRNAs as potential biomarkers for detecting risk of SGA

Small-for-gestational-age fetuses (SGA) (birthweight <10th centile) are at high risk for stillbirth or long-term adverse outcomes. To identify maternal plasma miRNAs as potential biomarkers for detecting risk of SGA, the study sampled 29 women (16 delivered normally grown babies and 13 delivered SGA (birthweight <5th centile)) and determined their plasma miRNA profiles (~800 miRNAs) by using the Nanostring nCounter miRNA assay. The comparative analysis between SGA and normal groups identified seven miRNAs at 12–14+6 weeks gestation. Four of these were technically validated by RT-qPCR. Differential expression of two miRNA markers; hsa-miR-374a-5p (p = 0•0176) and hsa-let-7d-5p (p = 0•0036), were validated in an independent population of 95 women (SGA n = 12, Control n = 83). In the validation cohort, which was enriched for SGA cases, the ROC AUCs were 0•71 for hsa-miR-374a-5p, and 0•74 for hsa-let-7d-5p, and 0•77 for the two combined