Incorporating first trimester analytes to predict delivery of a large for gestational infant in women with impaired glucose tolerance.
To investigate first trimester maternal characteristics of women with impaired glucose tolerance that deliver large for gestational age (LGA) infants. Nested analysis from a prospective study of singleton pregnancies enrolled at first trimester. We studied women with an abnormal 1 h glucose challenge test that had normal follow-up oral glucose tolerance testing. Maternal characteristics, ultrasound parameters and serum analytes were stratified by subsequent delivery of an LGA infant. Parameters identified as significant on univariate analysis were used for a derivation of prediction by logistic regression. Odds ratio and prediction performance was determined using receiver operator curve (ROC) statistics. A total of 33/114 (28.9%) women meeting the criteria delivered LGA infants. Maternal height (cm), and first trimester pregnancy-associated protein-A and free β-hCG (MoM) predicted delivery of an LGA infant (ROC area under curve 0.73; 95% CI 0.63-0.83). At a cutoff value of 0.172 the prediction rule achieved 91% sensitivity, 44% specificity, 41% positive predictive and 92% negative predictive value. Maternal height and first trimester high free β-hCG and PAPP-A levels may be used as predictors for delivery of LGA infants in women with impaired glucose tolerance.