Review Household air pollution and stillbirths in India: Analysis of the DLHS-II National Survey P.V.M. Lakshmi a,n , Navkiran Kaur Virdi a , Atul Sharma a , Jaya Prasad Tripathy a , Kirk R. Smith b , Michael N. Bates b , Rajesh Kumar a a School of Public Health, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India b School of Public Health, University of California, Berkeley, CA 94720-7360, USA article info Article history: Received 23 August 2012 Received in revised form 23 November 2012 Accepted 5 December 2012 Available online 31 January 2013 Keywords: Biomass fuel Kerosene Cooking fuel Stillbirths Indoor air pollution abstract Background: Several studies have linked biomass cooking fuel with adverse pregnancy outcomes such as preterm births, low birth weight and post-neonatal infant mortality, but very few have studied the associations with cooking fuel independent of other factors associated with stillbirths. Method: We analyzed the data from 188,917 ever-married women aged 15–49 included in India’s 2003–2004 District Level Household Survey-II to investigate the association between household use of cooking fuels (liquid petroleum gas/electricity, kerosene, biomass) and risk of stillbirth. Prevalence ratios (PRs) were obtained using Poisson regression with robust standard errors after controlling for several potentially confounding factors (socio-demographic and maternal health characteristics). Results: Risk factors significantly associated with occurrence of stillbirth in the Poisson regression with robust standard errors model were: literacy status of the mother and father, lighting fuel and cooking fuel used, gravida status, history of previous abortion, whether the woman had an antenatal check up, age at last pregnancy 435 years, labor complications, bleeding complications, fetal and other complications, prematurity and home delivery. After controlling the effect of these factors, women who cook with firewood (PR 1.24; 95% CI: 1.08–1.41, p ¼0.003) or kerosene (PR 1.36; 95% CI: 1.10–1.67, p ¼0.004) were more likely to have experienced a stillbirth than those who cook with LPG/electricity. Kerosene lamp use was also associated with stillbirths compared to electric lighting (PR 1.15; 95% CI: 1.06–1.25, p ¼0.001). The population attributable risk of firewood as cooking fuel for stillbirths in India was 11% and 1% for kerosene cooking. Conclusion: Biomass and kerosene cooking fuels are associated with stillbirth occurrence in this population sample. Assuming these associations are causal, about 12% of stillbirths in India could be prevented by providing access to cleaner cooking fuel. & 2012 Elsevier Inc. All rights reserved. 1. Introduction Worldwide, the focus of child health has remained on child survival, stillbirths remain mostly ignored (Froen et al., 2011). At least 2.65 million stillbirths were estimated globally in 2008. Ninety eight percent of them occur in low and middle-income countries (Cousens et al., 2011). However, only limited information is available on the risk factors associated with stillbirths in developing countries. Several studies have associated biomass cooking fuel with adverse pregnancy outcomes like preterm births, low birth weight and post- neonatal infant mortality but few studies have investigated associations between sources of household air pollution and still- births at the population level. Biomass smoke contains a number of harmful air pollutants, including respirable particulate matter, carbon monoxide (CO), nitrogen oxides (NO x ), formaldehyde, benzene, 1,3 butadiene, polycyclic aromatic hydrocarbons, and many other toxic organic compounds (Bruce et al., 2000). Inefficient, unvented household stoves and chulhas 1 coupled with poor ventilation increase the indoor concentration of these pollutants manifold. There are possible mechanisms by which biomass smoke may cause adverse pregnancy outcome like stillbirths. CO undoubtedly plays a role but the role of other pollutants like particulate matter should not be overlooked. Biomass smoke also contains the same pollutants as seen in tobacco smoke and ambient air pollution, which are established as risk factors for stillbirths. Thus the role of household biomass smoke Contents lists available at SciVerse ScienceDirect journal homepage: www.elsevier.com/locate/envres Environmental Research 0013-9351/$ - see front matter & 2012 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.envres.2012.12.004 n Corresponding author. E-mail addresses: pvm_lakshmi@yahoo.com (P.V.M. Lakshmi), kiranjas@gmail.com (N.K. Virdi), dr.atulsharma@hotmail.com (A. Sharma), ijay.doc@gmail.com (J.P. Tripathy), krksmith@berkeley.edu (K.R. Smith), m_bates@berkeley.edu (M.N. Bates), dr.rajeshkumar@gmail.com (R. Kumar). 1 Earthen stoves. Environmental Research 121 (2013) 17–22