Objective. To compare neonatal morbidity and mortality between late-preterm intrauterine growth-restricted (IUGR) and appropriate-for-gestational-age (AGA) infants of the comparable gestational ages (GAs). Methods. We retrospectively analyzed neonatal morbidity and mortality of 50 singleton pregnancies involving fetuses with IUGR delivered between 34 and 36 6/7 weeks of GA due to maternal and/or fetal indication. The control group consisted of 36 singleton pregnancies with spontaneous preterm delivery at the same GA, in which the infant was AGA. Categorical data were compared between IUGR and AGA pregnancies by analysis and Fisher's exact test. Ordinal measures were compared using the Kruskal-Wallis test. Results. The length of stay of newborns in the nursery, as well as the need for and duration of hospitalization in the neonatal intensive care unit, was longer in the group with IUGR. Transient tachypnea of the newborn or apnea rates did not differ significantly between the IUGR and AGA groups. IUGR infants were found to be at a higher risk of intraventricular hemorrhage. No respiratory distress syndrome, pulmonary hemorrhage or bronchopulmonary dysplasia was observed in either group. The frequency of sepsis, thrombocytopenia and hyperbilirubinemia was similar in the two groups. Hypoglycemia was more frequent in the IUGR group. No neonatal death was observed. Conclusion. Our study showed that late-preterm IUGR infants present a significantly higher risk of neonatal complications when compared to late-preterm AGA infants. 1. Introduction Prematurity is the leading cause of neonatal morbidity and mortality [1, 2]. Another important cause of perinatal morbidity and mortality is intrauterine growth restriction (IUGR), a condition in which the fetus is undernourished for gestational age [3]. Normally, IUGR is present in only a small percentage of deliveries, but an increased frequency has been observed among women who go into preterm labor followed by premature delivery [4]. Late-preterm birth is defined as birth between 34 weeks and 36 6/7 weeks of gestation [5]. During the past decade, the proportion of all U.S. births defined as late-preterm births has increased by 16% [6]. The overall rate of preterm births in the United States increased from 10.9% in 1990 to 12.8% in 2007, an increase of 16.6% [7]. This increase was mainly due to an increase in late-preterm births. In Brazil, approximately 88% of the 188,223 pre-term births recorded in 2005 occurred at an gestational age above 32 weeks [8]. The prevalence of IUGR is high in high-risk pregnancies. As a
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