OBJECTIVE: To evaluate the association between leptin level, adiponectin level, gestational weight gain, maternal constitutional factors, and the weights at birth and at 1 year of age in infants born to women with gestational diabetes mellitus (GDM). STUDY DESIGN: Fiftyone women with GDM were recruited from June 2011 to September 2011. Leptin and adiponectin levels in maternal and cord blood were measured and their correlations with infant's birth weight and weight after 1 year were evaluated using Pearson correlation analysis. The weight correlations were also determined with maternal constitutional factors. RESULTS: The neonatal birth weight positively correlates with cord blood leptin (r=0.316, p=0.024) and adiponectin (r=0.855, p =0.026) levels. One-year-old infant's weight correlates only with the cord blood adiponectin level (r=0.753, p=0.036). The infant's birth weight had positive correlations with maternal constitutional factors such as prepregnancy weight (r=0.340, p=0.015), prepregnancy BMI (r=0.289, p=0.040), prepartum weight (r=0.404, p=0.003), prepartum BMI (r=0.348, p=0.012), and gestational weight gain (r= 0.280, p=0.047). CONCLUSION: The infant's birth weight is closely associated with cord blood levels of both leptin and adiponectin and with pre gravid and prepartum maternal obesity. The 1-year weight of infants born to GDM mothers is only associated with levels of adiponectin in cord blood.