ARG1 and vitamin D deficiency: Notably, our peripheral blood transcriptome analysis of spontaneous preterm birth (sPTB: 24–32 wga vs Term: > 37 wga) and vitamin D insufficiency status (< 30 ng/mL) in mothers from the VDAART revealed CRISP3, ARG1, and MMP8 as highly connected genes in the overlapping module48.