Health Impacts of Air Pollution Exposure During Pregnancy

Letizia Airoldi, Biking through Pollution_ 2011, CC BY-NC-SA 2.0.

Letizia Airoldi, Biking through Pollution, 2011, CC BY-NC-SA 2.0

Air pollution is now the world’s largest single environmental health risk. WHO reports that air pollution exposure caused deaths of 7 million people 2012, or one in eight of total global deaths. Deaths among pregnant women, children and adolescents account for more than one third of the global burden of premature mortality. Children in developing countries are eight times more likely to die before they reach the age of five. Air pollution exposure causes health impacts that significantly differ across different population groups, among which pregnant women and infant might be the most vulnerable population.  

Worldwide, air pollution-related disease and death are distributed unequally. The huge burden of disease affects mainly low- and middle-income countries in South-East Asia and Western Pacific Regions, with a total of 3.3 million deaths linked to indoor air pollution and 2.6 million deaths related to outdoor air pollution. Most of the low- and middle-income countries have urgent needs related to depressed economies, dense populations, heavy traffic, less access to clean energy, as well as little investment in pollution control and weak environmental legislation. These factors combined create high air pollution levels in under-resourced countries. China is one country with dense population and heavy air pollution. In 2015, none of 366 air monitored cities in China met the WHO standard (yearly average PM2.5: 10ug/m3). Beijing had 45 days with an average PM2.5 concentration higher than 150ug/m3 in 2014.

This cohort study is designed to characterize the burden of pregnant women’s air pollution exposure and explore how it might affect miscarriage, gestational complication, birth outcomes and infant health. Intrauterine exposure to air pollution has been hypothesized to impart multiple-level health threats. First, airborne insults may cause pregnancy complications which are closely related to maternal and neonatal mortality. Second, airborne insults can interfere fetus development, lead to loss of pregnancy and affect birth outcome. Third, intrauterine exposure may also influence neonatal survival, infant development as well as the potential of developing diseases in adulthood. The proposed study aims to address environmental inequity in this vulnerable population. Project team members will recruit and follow-up 200 pregnant women from participating hospitals in Beijing. The aims of the pilot study include: 1) Recruit pregnant women from each participating hospital and retain the cohort through the follow-up period; 2) Assess the feasibility of using personal air sensor in characterizing maternal air pollution exposure at each trimester; 3) Collect and process biological samples.