In Mexico, there is still no consensus of a criteria for the diagnosis of Gestational Diabetes Mellitus (GDM). The objective was to compare characteristics among GDM diagnostic criteria by the International Association of Diabetes and Pregnancy Study Groups (IADPSG) and the National Institute for Health and Clinical Excellence (NICE) in Mexico. A prospective and descriptive study was conducted in the Northeast region of Mexico. Prevalence, risk factors, maternal-fetal outcomes were evaluated. GDM prevalence was 44.5% by IADPSG and 37.5% by NICE. The analysis of risk factors and outcomes tended to be equal between criteria; nonetheless, the use of only IADPSG or NICE criteria limited the number of patients diagnosed with GDM, leading to a percentage of misclassified cases. IADPSG criteria seem to have fewer limitations to identify GDM patients than NICE due to the characteristics of the cohort. Although, determining in parallel NICE criteria, could be complementary for GDM diagnosis in Mexico. As conclusions, we propose the assessment of both criteria (IADPSG and NICE) to identify the largest number of women at risk of GDM. The lack of significant differences in outcomes between criteria reflects the importance of opportune treatment for GDM patients, which is not administered in a percentage of GDM missed cases when only one criterion is used.