Second-Hand Smoke Exposure inside the House and Adverse Birth Outcomes in Indonesia: Evidence from Demographic and Health Survey 2017

ObjectivesSecond-hand Smoke (SHS) during pregnancy among non-smoking women associates with mortality and morbidity risks in their infants. However, little is known about the SHS inside the house and the adverse birth outcomes. This study aims to assess the prevalence, level, and frequency of SHS exposure inside the house and investigate their associations with birth outcomes. MethodsWe use the Indonesian Demographic and Health Survey (IDHS) 2017, a large-scale nationally representative survey. Women aged 15 to 49 years who had given birth in the last five years before the study and their husbands were interviewed (n=19,935). Three dependent variables included Low Birth Weight (LBW), size at birth, and birth weight. ResultsSeventy-eight percent of mothers exposed to SHS inside home, of whom 7.2% had LBW children. Compared to non-SHS exposure mothers, those exposed to SHS were younger, had first birth before 20 years old, married, lower educated, non-worker, lived in rural, grand multipara, had pollution from cooking fuel, cook in a separate building, had higher risk of delivering lower birth weight (aOR=1.16, 95% CI: 1.02, 1.33), and smaller baby (aOR=1.51, 95%CI: 1.35, 1.69), even after the controlling for the covariates. We identified the inverted U-shaped association for SHS exposure frequency. Similar risk was also observed among mothers exposed with SHS on a daily basis compared to those who are not exposed. Conclusion for PracticeExposure to SHS inside home was significantly associated with LBW and size at birth. Given the high smoking prevalence, relevant policy and health promotion are needed. Significance StatementAdverse birth outcomes, such as low birth weight and smaller size at birth, may not be clearly explained by the second-hand smoke (SHS) exposure from a smoking husband alone. Our findings show that the prevalence of SHS inside the house in Indonesia is 78.4%. Pregnant women exposed to anyone who smokes in the household may be linked to poor birth quality, including low birth weight and smaller size at birth in their babies, after adjustment for risk factors. The effects of SHS exposure on birth outcomes are further exacerbated by daily SHS exposure.