Prenatal exposure to indoor air pollution and the risk of Low Birth Weight: A case-control study in a rural maternity hospital in Ramanagara district, Karnataka

Abstract

Background: In India, according to National Family Health Survey 4, the incidence of low birth weight was 18%. One of the factors that has emerged as a risk factor for low birth weight (LBW) is indoor air pollution. Objectives: To estimate the risk of low birth weight with prenatal exposure to indoor air pollution, in a rural area of south Karnataka. Study design: Case-control study. Study setting: The study was conducted in a Maternity hospital in a rural area of Ramnagara District in south Karnataka for two months. Participants: Women who delivered live singleton infants with LBW (birth weight < 2500g irrespective of gestational age) were considered “Cases”. “Controls” included women who delivered single live infants weighing ³ 2500g. Methods: Subjects were administered a pre-tested, face-validated structured questionnaire, with socio-demographic and obstetric information, exposure to various sources of indoor air pollution as well as environmental factors contributing to indoor air pollution. Main outcome measures: Odds ratio and adjusted odds ratio for various sociodemographic and environmental factors contributing to LBW. Results: Absence of exhaust ventilation in the kitchen, OR=3.76 (1.09-13.03), regular use of incense, OR=4.94 (1.12-21.73) and lack of cross ventilation in the house, OR=4.65 (1.60-13.51) were identified to be the main risk factors associated with LBW. Conclusions: Prenatal exposure to indoor air pollution carried a higher risk of LBW. Pregnant women need to be educated regarding the harmful effects of burning incense at home and the dangers of poor ventilation, and their effect on the birth weight of newborns.