Table 3. Performance of “FPG at the FPV” algorithm and “age plus FPG at the FPV” algorithm to screen Gestational Diabetes Mellitus (GDM) in the training cohort and in the validation cohort.

Algorithm	Threshold to exclude GDM	Training cohort			Validation cohort
		OGTT (%)	Sensitivity (%)	Specificity (%)	OGTT (%)	Sensitivity (%)	Specificity (%)
FPG at the FPV	< 79	68.8	92 (83.4–97)	100	72.8	89 (62.1–96.8)	100
“Age plus FPG at the FPV”	< 114	58.5	90.7 (81.7–96.2)	100	59.6	92.3 (74.9–99.1)	100

Estimates (95% confidence interval) were shown.

FPG, fasting plasma glucose; FPV, first prenatal visit; GDM, gestational diabetes mellitus; OGTT, oral glucose tolerance tests; FPG is in conventional units (mg/dL).