Megan Carpentier reports for RH Reality Check on the recent Womens eNews Summit on Black Maternal Health.
Dr. Michael Lu, a UCLA Associate Professor of Obstetrics and Gynecology and Public Health, began his presentation at Women’s eNews on infant mortality rates that he termed “disgraceful” with a promise. It was not his promise, but the promise of America.
We hold these truths to be self-evident, that all men [and women] are created equal…
In that promise, he said, America is failing. To illustrate the extent of its failure, he, Kimberly Seals Allers, the editorial director of the Black Maternal Health Project and Tonya Lewis Lee, the national spokesperson for the “A Healthy Baby Begins With You” campaign, went over some of the sobering statistics about infant and maternal mortality in the African-American community. African-American children are twice as likely as white children to be born at a low birth-weight, twice as likely to be born premature and more likely to die in infancy. African-American women are three to four more times likely to die in childbirth as white women.
Lu challenged the audience to rethink some of the typical assumptions people — and even scientists — make when confronted with the disparate pregnancy outcomes for women of color. As Allers noted, unlike with white women, education and socioeconomic status play no discernable effect on reducing infant mortality or low birth weight in the African-American community.
Lu first challenged the assumption that those of African descent are genetically predisposed to higher incidence of infant mortality by highlighting statistics that show, in fact, the rate of infant mortality among foreign-born black women is significantly lower than for U.S. born black women. He challenged the assumption that it has to do with an increased incidence of unhealthy gestational behavior by mothers; in fact, more white women report smoking during pregnancy, a known risk factor, and even white women who smoked had lower infant mortality rates than African-American women who did not. Is this the result of disparate access to prenatal care? Not according to Lu, who showed that African-American women who receive prenatal care in the first trimester experience higher rates of infant mortality than white women who did not and that, although African-American women and Hispanic women receive comparable levels of prenatal care, the infant mortality rate for Hispanic women is much lower.
And, as Allers alluded to earlier, there is little correlation between socioeconomic status and infant mortality rates. Statistics show that even college-educated African-American women continue to have significantly higher infant mortality rates than white women without a college education. Stressful life events during pregnancy, which can caused increased levels of damaging stress hormones to reach the fetus, were not correlated with premature birth, infant mortality of low birth rates, all areas in which there remain significant disparities between African-American and white women. Even the screening and treatment programs for infections that have been standard in prenatal care for a decade show little effect on infant mortality, preterm delivery or low birth rate weights.
Al though it might seem fair to conclude that while no one of these factors can completely explain the significant disparities in birth outcomes between African-American and white women, a 1997 study that controlled for 46 different risk factors in 1,000 pregnant women showed that, even in combination, those risk factors accounted for less than 10 percent in the variances in the rates of low birth weight.
Lu said, however, that the research increasingly reflects the fact that “less than nine months of prenatal care cannot eliminate a lifetime of health disparities.” For Lu, a starting point was the Barker Hypothesis, which linked low birth weight to later incidence of heart disease, high blood pressure and diabetes. Scientists now believe this indicates that one’s organs are, in effect, programmed during fetal development and that programming can have lifelong effects.
How does that explain the racial disparities in pregnancy outcomes? Scientists know that stress on the mother causes her to produce stress hormones, which can adversely effect the development of a fetus’ hippocampus and amygdale, two areas of the brain associated both with the fight-or-flight response, memory formation and anxiety. Prolonged stress in the mother decreases the sensitivity of those two areas of the brain to mediate its own stress response, which has been linked to, among other things, ADHD.
A study of epigenetics offers yet another clue: epigenetics is the study of the chemicals that mediate the expression of genes — or, in Lu’s words, a volume switch that helps decide how much of a say any individual gene is allowed. Stress can cause the fetus to develop the chemicals that turn individual genes on or off (or up or down), which can, in turn, create exacerbate existing genetic risk factors for disease.
Lu and other scientists also hypothesize that chronic stress takes a toll on women over time, damaging the necessary balance of the fight-or-flight response (in which the body ramps up and then comes back down) through overexposure to stress hormones. The correlation in adults between chronic stress and everything from hypertension to insulin resistance to reduced immune responses is well established. But the body’s response to chronic stress, it seems, can also harm a fetus by subjecting it to the same negative biological conditions of chronic stress, which are different than responses to individual stressing events. The ongoing exposure to large quantities of stress hormones is thought to be a leading cause in disparate pregnancy outcomes, as stress is known to be a complicating factor for pregnancy.
If the leading hypothesis is that chronic stress is a large and limiting factor in racial disparities in pregnancy outcomes, the question then becomes: what large stressor is present in African-American women that doesn’t exist for white women? And the obvious answer, of course, is racism. Statistics show that women with very low birth weight babies were three times as likely to have experienced interpersonal racism than women with children of normal birth rates. Foreign-born black women see their rates of infant mortality rise to the same level as U.S.-born black women within a generation.
Lu and his colleagues have a 12-point plan for beginning to address the social and health disparities they think are intimately linked to adverse pregnancy outcomes for African-American women. As Lu told his audience, “There is a misconception that one visit before a planned pregnancy is preconception care.” He knows that he cannot resolve the issues that occur as the result of years of stress and poor health in less than nine months serving as someone’s obstetrician, and without addressing those lifelong issues, he cannot make an impact on pregnancy outcomes. He and Lewis Lee think that programs like hers, which focus on health and peer education among students in underserved communities to try to have an impact on their outcomes later in life, are important, as are efforts to focus society on the necessary social, institutional and health systems to allow more African-American children (and their mothers) survive and thrive.