Chaiworapongsa et al. performed a prospective cohort study of 12 pregnant women and found that a reduced PlGF to soluble vascular endothelial growth factor receptor-1 (sVEGFR-1: also known as soluble fms-like tyrosine kinase-1) ratio at 34 weeks had a likelihood ratio of 14 for the prediction of subsequent stillbirth [120]. This evidence concerns the gene PGF and Stillbirth.