Invited Commentary: Troubling Trends in Birth Weight.

Birth weight is a strong predictor of the health of newborns. Consequently, the report by Catov et al. in this issue of the Journal (Am J Epidemiol. 2016;183(1):15-23), in which they showed downward trends in birth weights in a Pittsburgh, Pennsylvania, hospital from 1997 to 2011, raises concerns. The widening gap reported between birth weights of babies born to white and African-American women could correspond to a widening gap in actual health outcomes. However, if the relation between birth weight and health outcomes is not causal, these trends may be epiphenomena of limited concern. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.