Screening for gestational diabetes mellitus by a model based on risk indicators: a prospective study

Objective This study was performed to prospectively evaluate a screening model for gestational diabetes mellitus on the basis of clinical risk indicators. Study design In a prospective multicenter study with 5235 consecutive pregnant women, diagnostic testing with a 2-hour 75-g oral glucose tolerance test was routinely performed in women with risk indicators and offered to women without risk indicators as part of the study. Results Forty-four percent of the women underwent testing, 43% declined participation, 6% did not speak Danish, and 7% could not be contacted. By extrapolation of the results from tested women to the whole group in question, a 2.4% prevalence of gestational diabetes mellitus was calculated. Sensitivity and specificity of the model was 80.6 (73.7-87.6) and 64.8 (63.5-66.1), respectively (95% CIs). Conclusion Under ideal conditions, sensitivity of the model was comparable with universal screening by fasting glucose or a 1-hour 50-g glucose challenge test. Both screening and diagnostic testing could be avoided in two thirds of all pregnant women.