Black women have worse IVF outcomes. New science helps explain why
A new study helps narrow down the reasons why Black people undergoing infertility treatment have fewer live births
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Over the past two decades, fertility experts have been grappling with a perplexing issue: why do Black individuals experience lower live birth rates following in vitro fertilization (IVF) compared to their white counterparts?
Several theories have been put forward. One reason might be that Black women experience higher rates of fibroids—benign tumors that can disrupt embryo implantation, a crucial step where the embryo embeds into the uterine lining. Another possibility is that their bodies are less responsive to IVF stimulation drugs, which are designed to induce the ovaries to produce multiple mature eggs for fertilization and subsequent embryo transfer.
Researchers at the University of Pennsylvania sought to dissect the IVF process in detail to identify the underlying causes. Their goal was to shed light on earlier studies that suggested Black women might require higher medication doses or produce fewer viable embryos.
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In their recent study published in Fertility and Sterility, researchers examined over 246,000 ovarian stimulation cycles, with 7 percent involving Black women. They compared responses across racial and ethnic groups and measured how many of these cycles resulted in live births. The study revealed that Black participants responded slightly better to ovarian stimulation drugs compared to other groups, and their eggs produced high-quality embryos suitable for implantation. This finding came after adjusting for factors like age at retrieval, body mass index, hormone levels, and infertility diagnoses, using data collected nationally between 2017 and 2019 by the Society for Assisted Reproductive Technology.
Despite these findings, Black women in the study had a lower live birth rate—about 45 percent compared to about 60 percent for white women.
“There’s clearly something happening that’s a roadblock to getting to the ultimate goal of bringing home a baby,” says Iris Tien-Lynn Lee, an ob-gyn at the University of Pennsylvania and the study’s lead author. “I think it’s an issue with implantation,” she speculates.
However, the exact cause remains unclear. The study authors noted potential factors like higher rates of uterine fibroids, exposure to endocrine-disrupting chemicals found in hair relaxers, and environmental contaminants, which are reportedly higher in Black populations.
“It’s a useful finding because it’s important to know there are more things to be investigated, but the most frustrating thing is that we don’t know what, exactly,” says Tia Jackson-Bey, a reproductive endocrinologist at Reproductive Medicine Associates of New York, who was not involved in the study. “We would need a more complete dataset to tease out any meaningful differences based on race,” she adds. Other promising research areas include examining the mental and physical health of those trying to conceive, including their uterine microbiome and cardiovascular health, which could affect uterine blood flow.
This information is also valuable for understanding how Black women are treated in the healthcare system, according to Tarun Jain, a professor of obstetrics and gynecology at Northwestern University Feinberg School of Medicine. “Black women in healthcare experience worse outcomes in general, whether it’s maternal mortality, infertility treatment, or preterm birth,” says Jain, who has examined structural barriers that contribute to disparities in fertility medicine. “We need to address these inequities at a broader level.”
This involves recognizing social determinants of health—nonmedical factors like racism, income inequality, and disparities in health insurance and access to nutritious food. Jain co-authored a 2020 study that found Black women were more likely to report their income and race as barriers to accessing infertility treatment. They also traveled twice as far as white women to reach fertility clinics.
According to a 2025 opinion from the practice committee of the American Society for Reproductive Medicine, these factors result in Black women being older when they first consult a fertility doctor and more likely to be diagnosed with diminished ovarian reserve—meaning their egg quality and quantity have declined with age, reducing the chances of successful treatment. (Jain is a member of this committee and contributed to the opinion report.)
“It’s important to know it’s not the stimulation drugs,” says Jain, referring to the University of Pennsylvania study. “But a lot more work needs to be done to understand the other factors and the implicit biases that may still exist.”
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