Gestational diabetes: fasting and postprandial glucose as first prenatal screening tests in a high-risk population.
OBJECTIVE
To evaluate the value of fasting (FPG) and 2-hour postprandial (PPG) plasma glucose as screening tests for gestational diabetes mellitus (GDM) in a high-risk population during early pregnancy.


METHODS
At their first prenatal visit, 708 women underwent FPG and PPG for universal screening for GDM, with the diagnosis confirmed by the 75-g oral glucose tolerance test (World Health Organization criteria). The area under the receiver operating characteristic curve (AUC) was used to analyze the performance of the 2 screening tests.


RESULTS
Of 184 (25.9%) women with GDM, 79 (42.9%) were identified before 18 weeks. The AUC for FPG to predict GDM was 0.579 (95% CI 0.531-0.627). Though a threshold of 85 mg/dL achieved minimally acceptable sensitivity, 79.9%, the corresponding specificity remained poor, 27.5%, with a false positive rate (FPR) of 72.5%. The AUC for PPG was 0.717 (95% CI 0.670-0.765); a cutoff of 95 mg/dL achieved a sensitivity of 79.9% and FPR of 53.1%.


CONCLUSIONS
Though GDM could be diagnosed in > 40% women in early pregnancy at their first prenatal visit, the poor specificity and high FPR of FPG and PPG, alone or in combination, make them unsuitable screening tests for GDM.
Agarwal
Mukesh M
MM
Department of Pathology, Faculty of Medicine, United Arab Emirates University, Al Ain. magarwal@uaeu.ac.ae
Dhatt
Gurdeep S
GS
Punnose
John
J
Zayed
Reem
R
D000293:Adolescent; D000328:Adult; D019540:Area Under Curve; D001786:Blood Glucose / Q000032:analysis*; D016640:Diabetes, Gestational / Q000097:blood / Q000175:diagnosis*; D005215:Fasting; D005260:Female; D005951:Glucose Tolerance Test / Q000379:methods* / Q000592:standards*; D006801:Humans; D008403:Mass Screening; D008875:Middle Aged; D019518:Postprandial Period; D011237:Predictive Value of Tests; D011247:Pregnancy; D012372:ROC Curve; D012307:Risk Factors; D012680:Sensitivity and Specificity
D001786:Blood Glucose