Characteristics of respiratory distress syndrome in infants of different gestational ages

Lung. 2013 Aug;191(4):425-33. doi: 10.1007/s00408-013-9475-3. Epub 2013 May 31.


Background: The purpose of this study was to compare the risk factors, clinical characteristics, and complications of respiratory distress syndrome (RDS) in infants delivered very preterm, late preterm, and term in order to help optimize the management of RDS in neonates.

Methods: A retrospective study was conducted on neonates admitted to the NICU between January 2006 and December 2010. The enrolled infants with RDS were categorized as very preterm (<32(0/7) weeks gestation), moderately preterm (32(0/7)-33(6/7) weeks), late preterm (34(0/7)-36(6/7) weeks), and term (37(0/7)-42(0/7) weeks). The rates, potential risk factors, clinical characteristics, and complications of RDS of these four groups were comparatively analyzed.

Results: There was an increasing trend in incidence of RDS among the NICU admissions annually. Caesarean section without labor was significantly associated with RDS in term and late preterm infants (P < 0.001). Rates of requirements for ventilator and pulmonary surfactant were similar in very preterm and term infants but significantly lower in late preterm infants (P < 0.001). The oxygenation index value was not substantially lower in late preterm and term infants compared to very preterm infants, and the arterial oxygenation efficiency was improved slowly (P < 0.001). Incidence of pneumonia and occurrence of pneumothorax were significantly higher in term infants (P < 0.001).

Conclusions: Term infants with RDS showed an association of RDS with caesarean section without labor and lung infection. These infants also showed slower improvement of oxygenation after surfactant administration and mechanical ventilation, and they experienced a high rate of pneumothorax complication, which was also noticed in late preterm neonates.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Cesarean Section / adverse effects
  • Chi-Square Distribution
  • China / epidemiology
  • Female
  • Gestational Age
  • Humans
  • Incidence
  • Infant, Extremely Premature
  • Infant, Newborn
  • Infant, Premature*
  • Intensive Care Units, Neonatal
  • Male
  • Odds Ratio
  • Pneumonia / epidemiology
  • Pneumothorax / epidemiology
  • Pulmonary Surfactants / therapeutic use
  • Respiration, Artificial
  • Respiratory Distress Syndrome, Newborn* / diagnosis
  • Respiratory Distress Syndrome, Newborn* / epidemiology
  • Respiratory Distress Syndrome, Newborn* / therapy
  • Retrospective Studies
  • Risk Factors
  • Treatment Outcome


  • Pulmonary Surfactants

Supplementary concepts

  • Respiratory Distress Syndrome In Premature Infants