LEP and fetal growth restriction: First, we did not assess important maternal information; it was reported that the mean maternal serum leptin concentration in pregnancies with IUGR was significantly higher than in normal pregnancies44; in addition, neonatal cord leptin concentrations correlate well with birth weight and BMI.45 As a result, the maternal serum leptin is an important covariate in the changes in serum leptin levels in neonates that should be considered in future studies.