PAPPA and gestational diabetes: Other individual studies examined the association between GDM and various other biomarkers, including hemoglobin, hematocrit, mitochondrial DNA, and hepcidin64; retinol-binding protein 465; the Quantose IR test66; sulphated progesterone metabolites67; lipohydroperoxides, malondialdehyde, and protein carbonylation68; magnesium69; 25 hydroxyvitamin D70; plasma glycated PC59 38,71; bile acids 52; PAPP-A, IGF-1, leptin, adipsin and resistin57; and the CREBRF rs373863828 allele.72