Features and outcome of pregnancies complicated by impaired glucose tolerance and gestational diabetes diagnosed using different criteria in a Spanish population

The main objective of this study was to determine the prevalence and risk of complications of a population of Spanish pregnant women with GDM diagnosed following the O'Sullivan-Mahan “standard” criteria, compared with pregnant women with GDM diagnosed using the “new” Carpenter-Coustan criteria. In Spain, limited data are published concerning as the prevalence of GDM and its morbidity. In this sense, the “new” criteria for GDM diagnosis has not been adopted in Spain due to the absence of adequate studies. We retrospectively reviewed all pregnancies handled at our center from 1999 to 2001 (n = 6248). Using the standard and the new criteria, the prevalence of GDM was 6.46 and 6.75%, respectively. GDM patients diagnosed using the new criteria showed the same pregnancy evolution that patients diagnosed with the classic criteria. Those patients complicated only with impaired glucose intolerance (IGT) (0.94%) showed a worst outcome. Based on the pregnancy evolution observed, it is not recommended that the new GDM diagnostic criteria be adopted in Spain. More accurate follow-up of patients with IGT is needed.