Glucagon-like peptide 1 (GLP-1) is a gut-derived peptide with insulin-like effects. Our aim was to analyze cord blood GLP-1 levels of macrosomic and appropriate-gestational-age (AGA) neonates from non-diabetic mothers. A case-control study was conducted with 22 term macrosomic neonates (birth weight >= 4000 g) and 22 AGA (birth weight > 10th percentile and < 4000 g) pregnancies. Cord blood GLP-1 levels of neonates were measured. There were no significant differences in maternal age, gestational age and gravida between the 2 groups. Umbilical cord blood GLP-1 levels were significantly lower in macrosomic neonates (6.9 +/- 2.9 pg/mL) compared with control group (10.3 +/- 3.7 pg/mL) (p = 0.002). Binary logistic regression analysis showed only the maternal BMI to be an independent statistically significant predictor of macrosomia (odds ratio = 2.459; 95 % CI, 1.170-5.170; P = 0.018). The results of our study revealed decreased GLP-1 levels in macrosomic neonates, and maternal BMI was an independent predictor of macrosomia.