This study investigated characteristics of term infants culture-evaluated for early-onset sepsis (EOS) in neonatal intensive care units (NICUs), frequencies of organisms causing EOS, and factors associated with EOS. EOS was most commonly caused by group B Streptococcus. Lower EOS risk was associated with low Apgar score, Cesarean delivery, small for gestational age, prenatal antibiotic exposure, and positive or unknown maternal GBS screening result. Increased risk was associated with prolonged rupture of membranes, maternal age <19 years, vasopressor treatment, and ventilator support.