Why do black women have worse IVF outcomes?

Black women have worse IVF outcomes. New science helps explain why

New study helps determine why Black people undergoing infertility treatment have fewer live births

By Sarah Elizabeth Richards edited by Lewis asked.

Over the past two decades, fertility specialists have grappled with a troubling question: Why do black people have lower live birth rates than white people after in vitro fertilization (IVF) treatment?

Researchers have proposed several explanations, such as that black women higher rates fibroids – noncancerous growths that can interfere with embryo implantation, the delicate process by which an embryo burrows into the lining of the uterus and remains there. Another possibility is that their bodies simply don’t respond as well to IVF stimulation drugs, drugs that cause the ovaries to simultaneously produce multiple mature eggs that are then inseminated to produce embryos that can be transferred to the uterus in hopes of establishing a pregnancy.

To determine the causes, researchers at the University of Pennsylvania sought to break down the IVF process step by step. They wanted to see if they could provide insight into previous inconsistent findings from other researchers, suggesting that black women needed higher doses of medication or generated fewer viable embryos.

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In their recent study, published in Fertility and Sterility, Researchers analyzed a total of more than 246,000 ovarian stimulation cycles, 7% of them in black women, to compare how women from different racial or ethnic groups responded and to measure how many of those cycles resulted in live births. The new analysis revealed that Black participants responded lightly better that people of other racial or ethnic groups took ovarian stimulation drugs, and their eggs produced high-quality embryos that could be used for implantation. That was after researchers adjusted participants’ age at collection, body mass index, hormone levels and infertility diagnoses in data collected nationally between 2017 and 2019 by the Society for Assisted Reproductive Technology, a U.S. professional organization that tracks IVF outcomes in fertility clinics.

Still, 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 going on that’s a barrier to achieving the ultimate goal of bringing a baby home,” says Iris Tien-Lynn Lee, a gynecologist at the University of Pennsylvania and lead author of the study. “I think it’s an implementation problem,” she hypothesizes.

But the exact cause is still unclear. The study authors also acknowledged the potential role of higher rates of uterine fibroids, as well as endocrine-disrupting chemicals, such as those found in relaxersand exposure to environmental contaminants that other studies have shown is higher in black populations.

“This is a useful finding because it’s important to know that there are more things to study, but the most frustrating thing is that we don’t know what exactly,” says Tia Jackson-Bey, a reproductive endocrinologist at Reproductive Medicine Associates in New York and an expert on access to fertility care, who was not involved in the study. “We would need a more comprehensive data set to highlight any significant differences based on race,” she says. Other promising areas of research include examining aspects of the mental and physical health of the person trying to become pregnant, including their uterine microbiome and cardiovascular health; the latter could affect uterine blood flow.

This information is also valuable because it provides insight into how black women are treated in the health care system, adds Tarun Jain, professor of obstetrics and gynecology at Northwestern University’s Feinberg School of Medicine. “Black women receiving health care generally experience worse outcomes, whether maternal mortality“, infertility treatment, or premature birth,” says Jain, who has written about the structural barriers that explain disparities in fertility medicine. “We need to address these inequalities on a broader level.”

This means recognizing the social determinants of health – the non-medical conditions that shape health, including racism, income inequality, and disparities in health insurance coverage and access to healthy food. Jain co-wrote a 2020 study which found that black women were more likely to report that their income and race were barriers to obtaining infertility treatment. They also traveled twice as far as white women to visit a fertility clinic.

According to a 2025 notice According to the American Society for Reproductive Medicine Practice Committee, due to factors such as these, black women are more likely than white women to be older when they first see a fertility doctor and are more likely to be diagnosed with diminished ovarian reserve, meaning the quality and quantity of their eggs have declined with age and the chances of treatment success are worse. (Jain is a member of the practice committee and helped develop the opinion report.)

“It’s important to know that these are not the stimulation drugs,” says Jain, referring to the findings of the University of Pennsylvania researchers. “But there is still much work to be done to understand other factors and implicit biases that may still exist.”