When Sarka Lisonkova and her colleagues set out to study disparities in the birth outcomes of people who’ve used methods like IVF, they figured that any inequities that existed would be narrower in this group. After all, it can be expensive to get pregnant with medical assistance, and wealth is tied to better outcomes.
Instead, the researchers reported Wednesday, the racial and ethnic disparities for some metrics were even wider for babies of parents who had used IVF or other fertility treatments than among children who were conceived “spontaneously.”
One key finding: while neonatal mortality rates were twice as high among spontaneously conceived children of Black women versus white women, they were four times as high among infants of Black women conceived through technologies like IVF, according to the researchers’ study, which was published in the journal Pediatrics.
“We were surprised,” said Lisonkova, an associate professor of obstetrics and gynecology at the University of British Columbia. In the paper, the researchers called for additional studies to reduce “risks among vulnerable women who use medically assisted reproduction.”
For the study, the researchers analyzed data from more than 7 million U.S. births from 2016 and 2017, focusing on single births and excluding twins and other multiple births. They compared outcomes from people who conceived spontaneously, those who used assisted reproduction technologies like IVF, and those who used other types of fertility aids, such as medication or insemination.
The researchers also found wider disparities in preterm birth (earlier than 34 weeks) and perinatal mortality among Hispanic mothers versus white mothers who turned to medically assisted reproduction generally, compared to the disparities between the groups when looking at spontaneously conceived children.
Higher rates of adverse outcomes among Black newborns — from infant death to preterm birth to low birth weight — are a prime example of the way systemic racism shapes health, experts say. Individual risk factors and socioeconomic status alone can’t fully account for those differences in outcomes, past studies have shown.
The new study was not designed to answer why the disparities might be greater among people who rely on medical assistance to get pregnant, but the researchers suggested that the same factors that drive disparities overall are at play.
“Racial and ethnic disparities in birth outcomes are not solely medical matters but rather symptoms of larger social, economic, and political factors,” they wrote. “Socioeconomic disadvantages, poor neighborhood conditions, lack of access to health care, psychosocial stress, racial discrimination, and systemic racism also contribute significantly to racial disparities in reproductive health.”
In general, getting pregnant with medical help is associated with higher rates of adverse birth outcomes, such as preterm birth and lower birth weight. And in the study, neonatal mortality among Black mothers was 0.5% in the spontaneous conception group and 1.6% in the IVF group. Among white mothers, the rate was 0.3% for both groups.
“Although assisted reproduction is generally safe, there is a known increased risk of adverse perinatal outcomes for all families who undergo assisted reproduction,” Kayla Karvonen, a neonatology fellow at UCSF, who was not involved with the new research, wrote in an email. “This study found that inequities persist even among a generally more privileged group, and the known risk for assisted reproduction is even higher for Black families compared to white families.”
Such findings highlight how technologies like IVF can’t mitigate the influence of structural racism on health outcomes, said Isabel Morgan, the director of the Birth Equity Research Scholars program at the National Birth Equity Collaborative, who was not involved in the new research.
“What is quite remarkable is seeing those inequities even more pronounced,” Morgan said.
As to why the disparities were wider, Morgan wondered if people from different racial and ethnic backgrounds turned to medical assistance with different causes of fertility issues, influencing the outcomes.
Karvonen, who is also the chair of a group called the Neonatal Justice Collaborative, offered another possible explanation.
“We know that both historically marginalized women and women who have medically assisted reproduction (MAR) are at higher risk of adverse birth outcomes,” Karvonen wrote in the email. “This study shows that the risk of being a part of both groups is only compounded on top of the underlying risk of being a part of either group alone.”
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