The rate of infants born at 34-36 weeks gestation has increased over the last 10 years. These babies are at higher risk of morbidity and mortality than full-term infants. At present, prenatal steroids are given until 34 weeks. The purpose of this study was to present the epidemiologic data of the late preterm infants and took for respiratory distress risk factors. This is a descriptive, Single-Center Study including 59, 55 and 72 children born at 34, 35 and 36 weeks gestation, respectively, in a level III centerin 2005 and 2006 for babies born at 34. weeks and in 2006 for the babies born at 35 and 36 weeks. Of the mothers who delivered at 34 and 35 weeks, 63% and 49%, respectively, had a morbidity. The cesarean-section delivery rate before labor was 36% for the infants born at 34 weeks and 25% for the infants born at 35 weeks. Prenatal steroids were used for 57% of the mothers who delivered at 34 weeks and for 27% of the mothers who delivered at 35 weeks. In the population of the babies born at 34. weeks, a mean delay between the last close of steroid and delivery was 18.9 days. Of the infants born at 34, 35 and 36 weeks, 27%, 1.8% and 8% suffered from respiratory distress. The mechanical ventilation Late was 8.5% and 5.5% for the infants born at 34 and 35 weeks' gestation. Surfactant was given to all infants born at 34 weeks who were intubated. Twenty percent of the 34-week-gestation infants and 12.7% of the 35-week-gestation infants required mechanical ventilation or noninvasive continuous positive airway pressure. Respiratory distress was mainly caused by respiratory distress syndrome or transient tachypnea of the newborn. There were no cases Of meconium aspiration syndrome. There was I ease of infection and 2 cases of pneumothorax. One-third of the infants born at 34-35 weeks were admitted to the neonatal intensive care Unit. The number dropped to 11% at 36 weeks' gestation. The gestational age was the only significant risk factor for respiratory distress. There was a strong tendency of the respiratory distress rate to decrease in the babies whose mothers had received steroids (odds ratio = 0.39, p = 0.06). (C) 2009 Elsevier Masson SAS. All rights reserved.