Maternal and Child Health Journal

, Volume 16, Issue 4, pp 745–746 | Cite as

Biases in Studying Gestational Weight Gain and Infant Mortality in US Birth Certificates

  • Lisa M. BodnarEmail author
  • Jennifer A. Hutcheon
  • Barbara Abrams

To the Editor:

In a study recently published in the Maternal and Child Health Journal, Davis and Hofferth presented an analysis of the association between total gestational weight gain (GWG) and risk of infant death in a random sample of 100,000 births from the National Center for Health Statistics 2002 Birth Cohort Linked Birth/Infant Death Data file [1]. We agree that investigating the link between GWG, a modifiable risk factor, and infant mortality using nationally-representative data is an important research priority. However, we believe that the data analysis as reported carries a high likelihood of bias, and that the results from this analysis should be interpreted with caution.

We have four major concerns with the analysis. First, the authors defined inadequate GWG based on the 2009 Institute of Medicine (IOM)-recommend ranges for total GWG at term [2], but applied these definitions to both preterm and term births. Preterm births in their analysis, therefore, were more likely...


Infant Mortality Gestational Weight Gain Birth Certificate Body Mass Index Category Prepregnancy Body Mass Index 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. 1.
    Davis, R. R., & Hofferth, S. L. (2012). The association between inadequate gestational weight gain and infant mortality among U.S. Infants born in 2002. Maternal and Child Health Journal, 16(1), 119–124.PubMedCrossRefGoogle Scholar
  2. 2.
    IOM. (2009). Weight gain during pregnancy: Reexamining the guidelines. Washington, DC: National Academies Press.Google Scholar
  3. 3.
    IOM. (1990). Nutrition during pregnancy. Washington, D.C.: National Academy Press.Google Scholar
  4. 4.
    Hutcheon J. A., Bodnar L. M., Joseph K. S., Abrams B., Simhan H. N., Platt R. W. (2012). The bias in current measures of gestational weight gain. Paediatr Perinat Epidemiol (Epub ahead of print). doi: 10.1111/j.1365-3016.2011.01254.x.
  5. 5.
    Callaghan, W. M., MacDorman, M. F., Rasmussen, S. A., Qin, C., & Lackritz, E. M. (2006). The contribution of preterm birth to infant mortality rates in the United States. Pediatrics, 118(4), 1566–1573.PubMedCrossRefGoogle Scholar
  6. 6.
    Centers for Disease Control and Prevention. (2012). National center for health statistics. Vitalstats January 17, 2012.
  7. 7.
    Chen, A., Feresu, S. A., Fernandez, C., & Rogan, W. J. (2009). Maternal obesity and the risk of infant death in the United States. Epidemiology, 20(1), 74–81.PubMedCrossRefGoogle Scholar
  8. 8.
    Nohr, E. A., Bech, B. H., Davies, M. J., Frydenberg, M., Henriksen, T. B., & Olsen, J. (2005). Prepregnancy obesity and fetal death: A study within the Danish National Birth Cohort. Obstetrics and Gynecology, 106(2), 250–259.PubMedCrossRefGoogle Scholar
  9. 9.
    Baeten, J. M., Bukusi, E. A., & Lambe, M. (2001). Pregnancy complications and outcomes among overweight and obese nulliparous women. American Journal of Public Health, 91(3), 436–440.PubMedCrossRefGoogle Scholar
  10. 10.
    Catalano, P. M. (2007). Management of obesity in pregnancy. Obstetrics and Gynecology, 109(2 Pt 1), 419–433.PubMedCrossRefGoogle Scholar
  11. 11.
    Bodnar, L. M., Siega-Riz, A. M., Simhan, H. N., Diesel, J. C., & Abrams, B. (2010). The impact of exposure misclassification on associations between prepregnancy bmi and adverse pregnancy outcomes. Obesity, 18(11), 2184–2190.PubMedCrossRefGoogle Scholar
  12. 12.
    Lash, T. L., Fox, M. P., Thwin, S. S., Geiger, A. M., Buist, D. S., Wei, F., et al. (2007). Using probabilistic corrections to account for abstractor agreement in medical record reviews. American Journal of Epidemiology, 165(12), 1454–1461.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Lisa M. Bodnar
    • 1
    Email author
  • Jennifer A. Hutcheon
    • 2
  • Barbara Abrams
    • 3
  1. 1.Departments of Epidemiology and Obstetrics, Gynecology, and Reproductive Sciences, Graduate School of Public Health and School of MedicineUniversity of PittsburghPittsburghUSA
  2. 2.Department of Obstetrics & GynaecologyUniversity of British Columbia, E421A Shaughnessy Building, BC Children’s & Women’s HospitalVancouverCanada
  3. 3.Division of Epidemiology, School of Public HealthUniversity of CaliforniaBerkeleyUSA

Personalised recommendations