Background: The long-standing difference in infant mortality in the United States between black and white infants has increased in recent years. To help identify the cause, we evaluated changes in birthweight distributions (BDs) and birthweight-specific mortality rates (BSMRs) among black and white infants born in the United States between 1983 and 1991. Methods: Using national linked birth and death certificate data, we limited analyses to singleton births that occurred in the United States to resident, non-Hispanic black and white women.
