A group of economists and an epidemiologist examined 50 million birth certificates to identify the reasons why more black babies die as infants than white babies. The upshot of their research? It’s not what you think.
Between 1983 and 2004, the rate of black babies dying before their first birthday dropped from 18.6 per 100,000 live births to 12.3, or by a third. Over the same period the rate of white infant deaths dropped by a slightly smaller percentage, from 9 to 5.3 per 100,000 live births. But that still means that black infants died at more than twice the rate that white infants did.
There have been many explanations offered for the difference in survival rates, including discrepancies in education, access to prenatal care, fatherly engagement, local healthcare options and wealth. But by analyzing the birth certificate data, the researchers were able to rule most of those out. “When we take out the factors we can observe—including mother’s age, education level, marital status and state of residence—the difference in the rate in which black and white infants die remained absolutely stable for two decades,” says Steven Haider, professor of economics at Michigan State University and one of the authors of the study. “We’ve made no progress in shrinking that part of the gap.”
But birth certificates do not list wealth or income, so the researchers haven’t entirely ruled out that white mothers might be richer and getting better healthcare, although they think they got close. “To some extent, education or marital status would control for that variable,” says John Goddeeris, also an economics professor at MSU and a co-author of the paper, which was published in the American Journal of Public Health.
While the gap in infant mortality by race didn’t shrink, the scientists say that the known contributors are starting to get addressed. For example, there is now little correlation between the survival rate of children and the education level of the mother. “It’s not that now black mothers have the same level of education as the white mothers,” says Goddeeris. “It’s that education doesn’t seem to count as much. But being black still matters. And why exactly that is, we don’t know.”
The researchers estimate that 74% of the black-white infant mortality gap cannot be accounted for by differences in observable factors. So even if policymakers could find a way to eliminate the inequities in education, paternal engagement and other factors the researchers accounted for, it would only reduce the gap by a quarter.
When pushed, Goddeeris, who notes he’s an economist not a medical professional, says much of the discrepancy seems to correlate with preterm birth and extremely low birth weight. Black moms have a higher rate of early delivery and low birth weight babies. It can’t just be prenatal care, however, because the birth certificate data listed in what trimester prenatal care started, and did not correlate with the early deliveries. “What we need is an understanding of that issue,” says Goddeeris. “We don’t have an answer for that.”
Goddeeris, Haider and colleagues are moving on to analyze the birth certificates for data about infant mortality among other ethnicities. Preliminary figures seem to suggest that Asians have a lower infant mortality rate than whites. Perhaps understanding what contributes to that trend could inform what’s driving the higher morality rates among black infants.