The role of vitamin D may be to modulate endothelial function as it is known to improve endothelial cell migration and proliferation through upregulated gene expression of matrix metalloproteinase 2 (MMP-2), an extracellular matrix-dissolving factor [13,14], suggesting that vitamin D levels should be measured when evaluating endothelial function and infertility. This evidence concerns the gene MMP2 and Infertility.