We analyzed deliveries at Los Angeles County+University of Southern California (LAC+USC) Medical Center between January 1,2001 and December 31, 2007. All liveborn singleton infants 34 0/7 - 37 6/7 weeks gestational age were included. We excluded multiple gestations, intrauterine fetal demise, and any infant with a known congenital anomaly. Data included maternal characteristics, such as age, gravidity, parity, mode of delivery, maternal medical conditions, such as diabetes and hypertensive disorders , as well as birth outcomes, such as birth weight and Apgar scores.