Black Preterm Babies Born Between 32-36 Weeks are 60% More Likely to Die Following Discharge

Findings from Racial and Ethnic Disparities in Outcomes through One Year of Life in Infants Born Prematurely: A Population-Based Study in California are described by lead author Kayla L. Karvonen. Additional authors include Kayla L. Karvonen, Rebecca J. Baer, Elizabeth E. Rogers, Martina A. Steurer, Kelli K. Ryckman, Sky K. Feuer, James G. Anderson, Linda S. Franck, Dawn Gano, Mark A. Peterson, Scott P. Oltman, Brittany D. Chambers, John Neuhaus, Larry Rand, Laura L. Jelliffe-Pawlowski, and Matthew S. Pantell.

Please describe your research findings.

In our study we found that after discharge from the hospital, rates of rehospitalization and infant mortality for preterm babies vary by race/ethnicity. We found that Black preterm infants born between 32-36 weeks were 60% more likely to die after being discharged from the hospital than White infants. Black and Hispanic very preterm infants were also more likely to be rehospitalized than White very preterm infants. All these findings were true even after controlling for the birth weight of the babies, maternal medical factors, and family socioeconomic status.

Our study does not tell us why we are seeing these findings. We suspect that there are other variables we did not include in the study that may be explaining this difference, such as other social determinants of health. Additionally, there are variables that are difficult to measure like structural racism -- racist policies and laws that lead to in unequal distribution of resources to minority communities-- and disparities in quality of care delivered in the NICU that are impacting the ability to survive and thrive after being discharged from the hospital for our smallest infants.

What is important or unique about this study?

There are very few studies that look at rehospitalization rates in premature infants. In fact, this is the biggest and most recent study that we are aware of looking at rehospitalization rates in premature infants. Previous studies have not found this difference. This may be because our study was larger and therefore had more power to find these disparities.

 What is already known about this topic, and how do your findings add to or change this existing knowledge?

The first step is acknowledging there is a problem and spreading awareness. The next step will be what can we do about it.

Kayla Karvonen, Researcher and Co-author

The first step is acknowledging there is a problem and spreading awareness. The next step will be what can we do about it. We have known for a long time that rates of prematurity, birthweight, and infant mortality rates differ by race and ethnicity. We know that Black birthing people are more likely to give birth to premature infants.

Recent work also found that the quality of care we deliver in California NICUs differs by race and ethnicity. Not much is known about premature infants after they are discharged home from the hospital and how their wellbeing is impacted by society as we know it. If these infants are more likely to be born premature, with low birth weights, with premature co-morbidities, how do these infants do overtime? Our study starts to answer this question. The next question to ask is why do some infants do better than others?

How does your research impact current clinical practice? How does your research impact patients?

This data serves as a red flag for us to ask more questions about why there are differences in such important outcomes and how we can better serve our patients. Understanding the why is extremely important, as this is how we approach next steps. Asking questions about the quality of care we deliver in the NICU to ensure our care is equitable, access to follow up appointments and subspecialists, access to medicine and equipment, access to resources families need are all first steps to closely looking at how we can deliver the best care we can and how we can best support our families both in and outside the hospital.


Kayla Karvonen
Kayla Karvonen,
UCSF Pediatrics Clinical Fellow

What should researchers/providers/patients/public health workers/etc. do as a result of these findings?

The first step is acknowledging there is a problem and spreading awareness. The next step will be what can we do about it. The findings in our study call for future studies to investigate why some infants outcomes are worse than others and what can we do to change this. How can we deliver anti-racist care both in and outside of the hospital to improve the future of our NICU graduates?

Learn More

Racial and ethnic disparities in preterm birth outcomes: a call to action for neonatal providers