“…As described in our previous study 21 , perinatal factors were chosen as potential confounders: maternal characteristics included age at delivery (<20, 25–35, and >35 years), marital status (married, unmarried, and other), highest maternal education (<10th, 10th −12th, and >12th grades), maternal smoking (0, 1–19 and 20 cigarettes per day during pregnancy), hypertensive disorders during pregnancy (none, moderate, and severe), socioeconomic status (comprised of 5 categories as assessed by the original CPP investigators) and maternal pregnancy BMI (<18, 18–25, >25), BMI gain during pregnancy (<3, 3–6, >6). Infant characteristics included race (white, black, and other race); sex (male and female); gestational age (as categorical variable), delivery method (vaginal, cesarean section and others), birthweight (<2500 g, 2500g-4000g, and >4000 g); and feeding method (exclusively breast, exclusively bottle, mixed feeding, and unknown).…”