These rank rankings are actually part of a long-term trend, with the U.S. dropping from 12th in 1960, to 19th in 1980, 30th in 2005 and 31st in 2008. At the same time, the U.S. IMR declined by almost 75% between 1960 and 2000 (from 26.0 to 6.9), but has been flat since 2000, declining by only 4% (6.9 to 6.6). Before 1997, the U.S. IMR was better than the OECD average, but since then the OECD average has improved while the U.S. IMR remained flat. As a result, in 2008 the U.S. IMR of 6.6 deaths per 1,000 births was 43% higher than the OECD average of 4.6 deaths.

Analysts have suggested a number of non-systemic reasons why the U.S. IMR is so much higher than rates found in other developed nations, including (1) inconsistent recording of live births, (2) different rates of low birth weight and short gestational age births, and (3) racial and ethnic IMR disparities. The CRS report found that reasons (1) and (3) were probably not primary causes of the high IMR, and focused on the problem of low birth weight, which is a leading cause of infant mortality and can be improved by providing health education and health care.

Perhaps not surprisingly, the CRS report found that similar differences among the U.S. states’ IMR numbers show a parallel divide, with 7 of the 10 states with INRs above 8.0 being in the South (Tennessee, North Carolina, South Carolina, Georgia, Alabama, Mississippi and Louisiana), where access to health care and health insurance is also lower than the rest of the country.

Indeed, it is hard to argue with a key point made by the report: “Researchers have found that IMRs are the lowest for infants born to women enrolled in private insurance, that IMRs are higher for women enrolled in Medicaid, and that IMRs are highest for infants born to women who were uninsured. Researchers also have found that access to primary care can influence the national IMR. In general, countries with more primary care services available have lower national IMRs. In addition, countries that have implemented health reforms to increase primary care access have lower IMRs after implementation.”

-Matt Bewig

To Learn More:

The U.S. Infant Mortality Rate: International Comparisons, Underlying Factors, and Federal Programs (by Elayne J. Heisler, Congressional Research Service) (pdf)