Early-term birth is a risk factor for wheezing in childhood: A cross-sectional population study

J Allergy Clin Immunol. 2015 Sep;136(3):581-587.e2. doi: 10.1016/j.jaci.2015.05.005. Epub 2015 Jun 24.


Background: Early term-born (37-38 weeks' gestation) infants have increased respiratory morbidity during the neonatal period compared with full term-born (39-42 weeks' gestation) infants, but longer-term respiratory morbidity remains unclear.

Objective: We assessed whether early term-born children have greater respiratory symptoms and health care use in childhood compared with full term-born children.

Methods: We surveyed 1- to 10-year-old term-born children (n = 13,361). Questionnaires assessed respiratory outcomes with additional data gathered from national health databases.

Results: Of 2,845 eligible participants, 545 were early term-born and 2,300 were full term-born. Early term-born children had higher rates of admission to the neonatal unit (odds ratio [OR], 1.7; 95% CI, 1.2-2.5) and admission to the hospital during their first year of life (OR, 1.6; 95% CI, 1.2-2.1). Forty-eight percent of early term-born children less than 5 years old reported wheeze ever compared with 39% of full term-born children (OR, 1.5; 95% CI, 1.1-1.9), and 26% versus 17% reported recent wheezing (OR, 1.7; 95% CI, 1.3-2.4). Early term-born children older than 5 years reported higher rates of wheeze ever (OR, 1.4; 95% CI, 1.05-1.8) and recent wheezing over the last 12 months than full-term control subjects (OR, 1.4; 95% CI, 1.02-2.0). Increased rates of respiratory symptoms in early term-born children persisted when family history of atopy and delivery by means of cesarean sections were included in logistic regression models.

Conclusion: Early term-born children had significantly increased respiratory morbidity and use of health care services when compared with full term-born children, even when stratified by mode of delivery and family history of atopy.

Keywords: Cesarean section; asthma; atopy; bronchodilators; gestational age; wheezing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cesarean Section / statistics & numerical data
  • Child
  • Child, Preschool
  • Cross-Sectional Studies
  • Family Health / statistics & numerical data
  • Female
  • Gestational Age*
  • Hospitalization / statistics & numerical data*
  • Humans
  • Infant
  • Male
  • Pregnancy
  • Respiratory Sounds / diagnosis*
  • Respiratory Sounds / physiopathology
  • Risk Factors
  • Term Birth