PurposeThe Cook Stove Pregnancy Cohort Study (CSPCS) was designed to assess the effects of biomass fuel use on household air pollution (HAP) as well as the effects of HAP (fine particulate matter, PM_2.5) on birth outcomes and acute lower respiratory infection (ALRI) among infants in Bangladesh.ParticipantsWe recruited 903 women within 18 weeks of pregnancy from rural and semiurban areas of Bangladesh between November 2016 and March 2017. All women and their infants (N=831 pairs) were followed until 12 months after delivery and a subset have undergone respiratory and gut microbiota analysis.MethodsQuestionnaires were administered to collect detailed sociodemographic, medical, nutritional and behavioural information on the mother–child dyads. Anthropometric measurements and biological samples were also collected, as well as household PM_2.5concentrations.Findings to datePublished work in this cohort showed detrimental effects of biomass fuel and health inequity on birth outcomes. Current analysis indicates high levels of household PM_2.5being associated with cooking fuel type and infant ALRI. Lastly, we identified distinct gut and respiratory microbial communities at 6 months of age.Future plansThis study provides an economical yet effective framework to conduct pregnancy cohort studies determining the health effects of adverse environmental exposures in low-resource countries. Future analyses in this cohort include assessing the effect of indoor PM_2.5levels on (1) physical growth, (2) neurodevelopment, (3) age of first incidence and frequency of ALRI in infants and (4) the development of the respiratory and gut microbiome. Additional support has allowed us to investigate the effect of in utero exposure to metals on infant neurodevelopment in the first year of life.