How Implict Bias Kills Black Babies

Brianna* is the kind of person you want in your corner—steady, kind, and hardworking. At 27, she had just been promoted to manager at the local hardware store in Boston in recognition of her commitment and competence. Around that time, she and her husband, Jayden, were elated to discover they were expecting their first child. He painted a mural in the nursery; she began a pregnancy journal to their baby. Then COVID hit.

Jayden was laid off, part of a wave of terminations that disproportionately affected workers of color. Brianna picked up extra shifts, pushing through early pregnancy nausea to keep them afloat. When she told her boss she was pregnant, he didn’t offer congratulations. Instead, he looked disappointed. “I had high hopes for you,” he said. “I took a chance making you manager.”

Brianna didn’t argue. She didn’t cry. She swallowed the comment, knowing how easily Black women are stereotyped as angry or difficult. She just worked harder.

When Brianna finally got in to see an obstetrician at 22 weeks, she was met with a professional but distant demeanor. The doctor spoke mostly to Jayden. When Brianna's braids brushed against the provider's arm, she pulled away slightly. And when Brianna admitted she hadn’t been taking prenatal vitamins—because some weeks, they had to choose between medicine and groceries—the doctor responded with clipped disapproval: “That’s not optional during pregnancy.”

Brianna left feeling ashamed. So when troubling symptoms emerged days later—blurred vision, sharp pain, difficulty breathing—she said nothing. She didn't want to be seen as irresponsible or overreacting.

At 27 weeks, she collapsed at work while unloading a shipment. At the hospital, Brianna noticed the nurse assigned to her seemed distant and disengaged. That evening, Brianna’s baby, Marcus, was delivered via emergency C-section. He lived for only three days.

What happened?

Brianna’s story is tragic, but sadly not unique. Many will attribute her loss to bad luck or even Brianna’s own actions. But when you understand the science, another picture comes into focus—one that implicates the very structure of our social systems, including healthcare and the unconscious biases embedded within. It wasn't one incident that killed little Marcus, but the weight of a thousand small insults, in everyday life and in healthcare.

Implicit bias—A hidden killer

The loss of a child is heartbreaking.

Source: Fizkes / Shutetrstock

In a recent study to appear in the journal BMC Medical Ethics, our lab at the University of Ottawa, examined whether anti-Black implicit bias at the state level predicted Black infant mortality across the United States. We used data from over 1.7 million Americans who took the Implicit Association Test (IAT), paired with publicly available infant mortality rates from the CDC’s WONDER database between 2018 and 2020. We controlled for explicit bias and for White infant mortality, to isolate the specific effects of unconscious anti-Black attitudes.

The results were striking: States with higher levels of implicit anti-Black bias had significantly higher rates of Black infant deaths—year after year. In fact, implicit bias alone explained up to 39% of the variation in Black infant mortality across states. These effects remained significant even after accounting for income, meaning that babies born to well-off Black families were also impacted.

And the bias isn’t just coming from the general public; healthcare professionals demonstrated similar levels of implicit bias.

Biases Lead to Microaggressions

It’s easy to think of microaggressions as just words—hurtful, yes, but not fatal. But this is the misconception many marginalized people must contend with daily. Microaggressions aren’t just psychologically painful, but they also erode physical health over time. Microaggressions influence how people are spoken to, how they are believed, how they are treated, and when, or whether, they receive medical care at all.

A study of 1.8 million births in Florida hospitals between 1992 and 2015 found that the mortality rate of Black newborns was threefold greater than that of White newborns (Greenwood et al., 2020). The same study also found that the Black infant mortality rate was reduced by 50% when the attending physician was Black.

For Black mothers and babies, the weight of microaggressions accumulates, not just in their minds but in their bodies. Stress adds up, and trust wears down. The slights become fatal.

Brianna did everything she was supposed to do. She worked hard. She stayed quiet. She deferred to authority. And still, her baby died.

Brianna’s story is not just about one baby or one family. It’s about an entire system that places all families of color at risk—Latinx, Indigenous, Asian, multiracial—anyone who doesn’t fit the mold of who medicine was originally built to serve. The consequences of implicit bias ripple across generations, harming not only those seeking care but those not yet born. Our research underscores the urgent need for systemic reform, including comprehensive anti-bias education and training for all healthcare providers, from doctors and nurses to front desk staff. This is not just about fairness—it is about survival. To reduce infant mortality and close racial health gaps, we must start by confronting the biases that continue to shape who lives and who dies.

Microaggressions are not simply minor inconveniences or political correctness run amok. They are signals of a deeper systemic cancer—one that, if unaddressed, will keep killing babies and breaking families. Our healthcare system must take seriously the role of racial bias—not just the overt kind, but unconscious, subtle, and everyday acts. Because tiny, precious lives depend on it.