Screening of gestational diabetes in Tuscany: results in 2000 cases

According to the guidelines of the "Third international workshop conference on GDM", we have examined 2000 pregnant women. The glucose challenge test (GCT) was positive in 408 cases (20.4%) and negative in 1592 (79.6%). The OGTT (Carpenter and Coustan's criteria) was performed in 647 pregnant women. GDM and IGGT prevalence was of 6.25% and 5.5% respectively and normal glucose tolerance (NGT) 88.25%. The GCT effectiveness for GDM and IGGT diagnosis is: sensibility 75.1%, specificity 44%, positive predictive value 46.4% and negative predictive value 74%. GDM and IGGT compared with NGT women were significantly older (p < 0.05) and prepregnancy BMI was higher (p < 0.01); the prevalence of previous macrosomia (p < 0.01), previous gestational diabetes (p < 0.01) and family history for diabetes mellitus (p < 0.05) was greater in GDM and IGCT. The prevalence of preterm delivery was higher in both GDM and IGCT (GDM 12.5% and IGGT 15.4% vs NGT 6%; p < 0.01), as well as the prevalence of cesarean sections (GDM 31.6% vs IGGT 23.5% and NGT 20.3%; p < 0.02), and the occurrence of macrosomia (GDM 27.6%, IGGT 16.6% and NGT 16.2%). In addition a higher prevalence (p < 0.01) of hyperbilirubinaemia, hypoglycemia and hypertrophy cardiomyopathy was observed in newborns from GDM women. Our data show that: GCT has a good specificity for GDM diagnosis, prevalence of GDM in our population is about 6%, GDM is still correlated to an elevated maternal and neonatal morbility.