Prenatal and Postnatal Household Air Pollution Exposures and Pneumonia Risk: Evidence From the Ghana Randomized Air Pollution and Health Study

Chest. 2021 Nov;160(5):1634-1644. doi: 10.1016/j.chest.2021.06.080. Epub 2021 Jul 21.


Background: Nearly 40% of the world's population is exposed daily to household air pollution. The relative impact of prenatal and postnatal household air pollution exposure on early childhood pneumonia, a leading cause of mortality, is unknown.

Research question: Are prenatal or postnatal household air pollution, or both, associated with pneumonia risk in the first year of life?

Study design and methods: The Ghana Randomized Air Pollution and Health Study enrolled 1,414 nonsmoking, pregnant women before 24 weeks' gestation with prospective follow-up to the child's age of 1 year. We measured 72-h personal household air pollution exposures, indexed by carbon monoxide (CO), four times prenatally and three times postnatally. Weekly fieldworker surveillance identified ill-appearing children for physician pneumonia assessment. We used quasi-Poisson models to examine associations between prenatal and postnatal CO and physician-diagnosed pneumonia and severe pneumonia. Sex-specific effects were examined.

Results: Of the 1,306 live births, 1,141 infants were followed up with 55,605 child-weeks of fieldworker surveillance. The estimated risk for pneumonia and severe pneumonia in the first year of life increased by 10% (relative risk [RR], 1.10; 95% CI, 1.04-1.16) and 15% (RR, 1.15; 95% CI, 1.03-1.28), respectively, per 1-part per million (ppm) increase in average prenatal CO exposure and by 6% (RR, 1.06; 95% CI, 0.99-1.13) per 1-ppm increase in average postnatal CO exposure. Sex-stratified analyses suggest that in girls, higher prenatal CO exposure was associated with pneumonia risk, while no association was seen in boys.

Interpretation: Prenatal household air pollution exposure increased risk of pneumonia and severe pneumonia in the first year of life. Clean-burning interventions may be most effective when begun prenatally.

Trial registry:; No.: NCT01335490; URL:

Keywords: household air pollution; pneumonia; prenatal and postnatal exposures; sex-specific effects.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Air Pollution, Indoor* / adverse effects
  • Air Pollution, Indoor* / analysis
  • Air Pollution, Indoor* / prevention & control
  • Carbon Monoxide / analysis*
  • Environmental Exposure* / adverse effects
  • Environmental Exposure* / analysis
  • Environmental Exposure* / prevention & control
  • Female
  • Ghana
  • Household Articles / standards*
  • Humans
  • Infant
  • Infant Health* / standards
  • Infant Health* / statistics & numerical data
  • Male
  • Needs Assessment
  • Particulate Matter / analysis
  • Perinatal Care / methods
  • Perinatal Care / statistics & numerical data
  • Pneumonia* / diagnosis
  • Pneumonia* / epidemiology
  • Pneumonia* / prevention & control
  • Pregnancy
  • Preventive Health Services / methods
  • Preventive Health Services / organization & administration
  • Risk Assessment
  • Rural Health


  • Particulate Matter
  • Carbon Monoxide

Associated data