Maternal insulin-like growth factors and insulin-like growth factor-binding proteins for macrosomia prediction in diabetic and nondiabetic pregnancy: A prospective study

ObjectiveAttributable to the insulin-like growth factor (IGF) axis involvement in fetal growth regulation, possible contribution of the maternal IGF axis to antenatal fetal macrosomia diagnosis is a subject of particular interest in diabetic pregnancy. MethodsA total of 130 women were prospectively enrolled in a longitudinal single-center cohort study. The four study groups were: type 1 diabetes (n = 40), type 2 diabetes (n = 35), gestational diabetes (n = 40), and control (n = 15). IGF-1 and IGF-2 and insulin-like growth factor-binding protein (IGFBP) 1, 3, 6, and 7 serum levels were analyzed in 11- to 14-week and 30- to 34-week samples with a specific immunoassay. ResultsIn mothers of large-for-gestational-age neonates (90th percentile), higher (median test) first-trimester IGF-1 (P = 0.007) and lower IGFBP-1 (P = 0.035) were observed. The IGF-1/IGFBP-1 ratio was positively associated with neonatal weight (r = 0.434, P < 0.001). Receiver operating characteristic analysis revealed an association between large for gestational age and the first-trimester IGF-1 (area under the curve [AUC] = 0.747, P < 0.001), IGFBP-1 (AUC = 0.334, P = 0.011), and IGF-1/IGFBP-1 ratio (AUC = 0.750, P < 0.001). IGF-1/IGFBP-1 ratio had better performance for prediction of birth weight over 4000 g (AUC = 0.822, P < 0.001). ConclusionThe authors detected different first-trimester IGF-1 and IGF-1/IGFBP-1 thresholds applicable for either supposition or rejection of macrosomia diagnosis. Further investigation is needed to determine how the maternal IGF axis can contribute to fetal macrosomia prediction.

Automated summary

This study investigated the relationship between maternal insulin-like growth factor (IGF) levels and fetal macrosomia. The authors found that higher levels of first-trimester IGF-1 and a higher IGF-1/IGFBP-1 ratio were associated with large-for-gestational-age neonates. The IGF-1/IGFBP-1 ratio showed better performance in predicting birth weight over 4000 g.