title: Prepregnancy Body Mass Index and Infant Mortality in 38 U.S. States, 2012-2013.
abstract: OBJECTIVE
  To estimate whether prepregnancy body mass index (BMI) is related to infant mortality and whether adherence to weight gain recommendations mitigates the relationship between BMI and infant mortality.
  
  
  METHODS
  This was a cohort study using 2012-2013 U.S. national linked birth certificate and infant death files for 38 states and the District of Columbia with the BMI measure, including 6,419,836 singleton births and 36,691 infant deaths (infant mortality rate 5.72/1,000). Prenatal weight gain in three categories was based on adherence to Institute of Medicine recommendations. The outcome measure was infant deaths in the first year of life subdivided into two time periods: neonatal (less than 28 days) and postneonatal (28 days to 1 year).
  
  
  RESULTS
  With normal prepregnancy weight as a reference, after adjustment, the odds ratio (OR) for an infant death rose from 1.32 (95% confidence interval [CI] 1.27-1.37) for mothers in the obese I category to 1.73 (95% CI 1.64-1.83) for obese III. Higher BMI was related to higher rates of both neonatal and postneonatal mortality. The adjusted OR for the risk of an infant death among singleton, term, vertex births for those gaining less than the recommended weight was 1.07 (95% CI 1.01-1.12) and 1.04 (95% CI 0.99-1.09) for those gaining more than recommended.
  
  
  CONCLUSIONS
  Even after controlling for multiple risks, prepregnancy BMI was strongly related to infant mortality. Efforts to lower the infant mortality rate may benefit from a focus on reducing obesity among women of reproductive age.
authors.affiliation: Boston University School of Public Health, Boston, Massachusetts; Maryland Population Research Center, University of Maryland, College Park, Maryland; and the Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, and San Francisco General Hospital, San Francisco, California.
authors.forename: Eugene
authors.initials: E
authors.lastname: Declercq
authors.forename: Marian
authors.initials: M
authors.lastname: MacDorman
authors.forename: Howard
authors.initials: H
authors.lastname: Cabral
authors.forename: Naomi
authors.initials: N
authors.lastname: Stotland
mesh_terms: D015992:Body Mass Index; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D009765:Obesity; D011247:Pregnancy; D011248:Pregnancy Complications; D014481:United States