Considering the importance of GDM and its complications and tactful prevention, and controversial results of studies on PAPP-A and GDM (19, 20), in addition to the introduction of a new and available predicting biomarker for GDM, routinely tested during the 11–14th weeks of gestation, the aim of this study was to determine the relationship between PAPP-A levels and GDM in women who referred to health centers affiliated to Qazvin University of Medical Sciences, Iran. The gene discussed is PAPPA; the disease is gestational diabetes.