title: The Human Cost of Tobacco Chewing Among Pregnant Women in India: A Systematic Review and Meta-analysis.
abstract: BACKGROUND
  In India, smokeless tobacco (SLT) use among pregnant women is high and its adverse effects on pregnancy outcomes have not been properly documented in.
  
  
  OBJECTIVE
  To collate available evidence on the association between SLT use and three adverse pregnancy outcomes, i.e. low birth weight, preterm birth and stillbirth among women in India.
  
  
  METHODS
  A systematic search was conducted in MEDLINE, IndMed, Web of Science, Google Scholar and major journals. Two authors independently reviewed the studies and extracted data.
  
  
  METHODS
  Inclusion criteria were English articles published till December 2014, case control, case cohort or cohort, and exposure and outcome variables meeting predefined criteria. Exclusion criteria were case series, case reports, cross-sectional designs, risk estimate not restricted/adjusted for smoking with or without adjustment for other factors and duplicate data. Qualitative synthesis was followed by meta-analysis. Attributable burden was estimated using the population attributable fraction method.
  
  
  RESULTS
  Pooled odds ratio was significant for all three outcomes: low birth weight (1.88, 95 % CI 1.38, 2.54), preterm birth (1.39: 1.01, 1.91) and stillbirth (2.85: 1.62, 5.01). We found that 0.87 million low birth weight babies, 0.19 million preterm births and 0.12 million stillbirths occurring annually in India could be attributed to maternal SLT use.
  
  
  CONCLUSIONS
  There was a suggestive evidence of SLT use associated with adverse pregnancy outcomes among women in India. Further studies in this field are required to generate more conclusive evidence.
authors.affiliation: Department of Community Medicine, Velammal Medical College Hospital and Research Institute, Madurai, India.
authors.forename: Rizwan A
authors.identifier: 0000-0002-3140-2614
authors.initials: RA
authors.lastname: Suliankatchi
authors.affiliation: Tobacco Free Initiative Unit, World Health Organization, Regional Office for South-East Asia, I.P. Estate, New Delhi, 110 002 India.
authors.forename: Dhirendra N
authors.initials: DN
authors.lastname: Sinha
keywords: Adverse pregnancy outcomes; India; Smokeless tobacco; Systematic review