Outcomes of early preterm birth and late-preterm infants admitted in the neonatal intensive care unit: a retrospective, single-center study

Objective: To study the prevalence of major short-term neonatal morbidity in cases early preterm birth, late preterm birth and term birth. Methods: This was a retrospective study of all spontaneous, early preterm birth (<34 weeks) and late preterm deliveries (34 0/7 to 36 6/7 weeks of gestation) admitted in the NICU during the years 2009. Multiple gestations and pregnancies complicated by preterm premature rupture of membranes (PROM) or maternal or fetal complications were excluded. Short-term neonatal outcome was compared with a control group of full-term deliveries admitted in the NICU at the same time. Results: Data on 34 spontaneous late-preterm (S-LPT), 36 spontaneous early-preterm (S-EPT) were compared with 45 term infants admitted to NICU. Majority of S-LPT infants were 36 weeks (35.3%), followed by 35 weeks (32.4%) and 34 weeks (32.4%), respectively. The median birth weight was 1249gr (+/- 440), 2238gr (+/- 560) and 3332gr (+/- 614) for the S-EPT, S-LPT and Term groups respectively. The stay in the NICU was significantly higher in the S-EPT compared to the S-LPT (21.8 days +/- 25 days vs 10 days +/- 13 days, P<0.0001) and in the S-LPT compared to Term group (10 days +/- 13 days vs 4 days +/- 8 days, P<0.008). The prevalence of respiratory distress syndrome, pneumothorax, intraventricular hemorrhage and sepsis in late preterm infants was significantly higher compared with term infants. The late-preterm group had a 10-fold higher risk of at least one morbidity compared to term group Conclusion: Late-preterm infants had a significantly higher incidence of respiratory morbidity and infection and had a significantly longer duration of hospital stay compared to term birth. Progress in the neonatal care has continually pushed back the limit of viability and significantly improved the survival of extremely preterm infants (1-3). Increasing survival rate of extremely preterm babies coupled with their increased hospital stays (4) has diverted the finite resources away from the infants born between 34 and 36 weeks of gestation (5,6). The care of these infants has slowly moved away from neonatal units to transitional care units and to rooming in with parents in many cases (7-9). Recent evidence (5,6,10,11) suggests that this group of infants is not near normal, and managing them on the basis of such a perception may be inappropriate. Epidemiologic data from developed countries indicate an increase in the gestation-specific neonatal mortality rate about 8 times when compared with term infants (12-15). In order to understand the prevalence of major short-term neonatal morbidity in cases early preterm birth, late preterm birth and term birth we analysis retrospectively all spontaneous, early preterm birth (<34 weeks) and late preterm birth (34 0/7 to 36 6/7 weeks of gestation) admitted in the NICU during the years 2009.