While the likelihood of a cesarean delivery usually drops as maternal education level increases, the disparities seen in cesarean rates between white and Black or Hispanic women actually increase with more maternal education, according to findings from a new study presented at the Pregnancy Meeting sponsored by the Society for Maternal-Fetal Medicine.
Typically, higher maternal education is associated with a lower likelihood of cesarean delivery, but this protective effect is much smaller for Black women and nonexistent for Hispanic women, leading to bigger gaps between these groups and white women, found Yael Eliner, MD, an OB-GYN residency applicant at Boston University who conducted this research with her colleagues in the OB-GYN department at Lenox Hill Hospital, New York, and Hofstra University, Hempstead, New York.
Researchers have previously identified racial and ethnic disparities in a wide range of maternal outcomes, including mortality, overall morbidity, preterm birth, low birth weight, fetal growth restriction, hypertensive disorders of pregnancy, diabetes, and cesarean deliveries. But the researchers wanted to know if the usual protective effects seen for cesarean deliveries existed in the racial and ethnic groups with these disparities. Past studies have already found that the protective effect of maternal education is greater for white women than Black women with infant mortality and overall self-rated health.
The researchers conducted a retrospective analysis of all low-risk nulliparous, term, singleton, vertex live births to US residents from 2016 to 2019 by using the natality database of the Centers for Disease Control and Prevention. They looked only at women who were non-Hispanic white, non-Hispanic Black, non-Hispanic Asian, and Hispanic women. They excluded women with pregestational and gestational diabetes, chronic hypertension, and hypertensive disorders of pregnancy.
Maternal education levels were stratified into those without a high school diploma, high school graduates (including those with some college credit), college graduates, and those with advanced degrees. The total population included 2,969,207 mothers with a 23.4% cesarean delivery rate.
Before considering education or other potential confounders, the cesarean delivery rate was 27.4% in Black women and 25.6% in Asian women, compared with 22.4% in white women and 23% in Hispanic women (P < .001).
Among those with less than a high school education, Black (20.9%), Asian (23.1%), and Hispanic (17.9%) cesarean delivery prevalence was greater than that among white women (17.2%) (P < .001). The same was true among those with a high school education (with or without some college): 22% of white women in this group had cesarean deliveries compared with 26.3% of Black women, 26.3% of Asian women, and 22.5% of Hispanic women (P < .001).
At higher levels of education, the disparities not only persisted but actually increased.
The prevalence of cesarean deliveries was 23% in white college graduates, compared with 32.5% of Black college graduates, 26.3% of Asian college graduates, and 27.7% of Hispanic college graduates (P < .001). Similarly, in those with an advanced degree, the prevalence of cesarean deliveries in their population set was 23.6% of whites, 36.3% of Blacks, 26.1% of Asians, and 30.1% of Hispanics (P < .001).
After adjusting for maternal education as well as age, prepregnancy body mass index, weight gain during pregnancy, insurance type, and neonatal birth weight, the researchers still found substantial disparities in cesarean delivery rates. Black women had 1.54 times greater odds of cesarean delivery than white women (P < .001). Similarly, the odds were 1.45 times greater for Asian women and 1.24 times greater for Hispanic women (P < .001).
Controlling for race, ethnicity, and the other confounders, women with less than a high school education or a high school diploma had similar likelihoods of cesarean delivery. The likelihood of a cesarean delivery was slightly reduced for women with a college degree (odds ratio, 0.93) or advanced degree (OR, 0.88). But this protective effect did not dampen racial/ethnic disparities. In fact, even greater disparities were seen at higher levels of education.
“At each level of education, all the racial/ethnic groups had significantly higher odds of a cesarean delivery than White women,” Eliner said. “Additionally, the racial/ethnic disparity in cesarean delivery rates increased with increasing level of education, and we specifically see a meaningful jump in the odds ratio at the college graduate level.”
She pointed out that the OR for cesarean delivery in Black women was 1.4 times greater than white women in the group with less than a high school education and 1.44 times greater in those with high school diplomas. Then it jumped to 1.69 in the college graduates group and 1.7 in the advanced degree group.
Higher maternal education was associated with a lower likelihood of cesarean delivery in white women and Asian women. White women with advanced degrees were 17% less likely to have a cesarean than white women with less than a high school education, and the respective reduction in risk was 19% for Asian women.
In Black women, however, education has a much smaller protective effect: An advanced degree reduced the odds of a cesarean delivery by only 7% and no significant difference showed up between high school graduates and college graduates, Eliner reported.
In Hispanic women, no protective effect showed up, and the odds of a cesarean delivery actually increased slightly in high school and college graduates above those with less than a high school education.
Eliner discussed a couple possible reasons for a less protective effect from maternal education in Black and Hispanic groups, including higher levels of chronic stress found in past research among racial/ethnic minorities with higher levels of education.
“The impact of racism as a chronic stressor and its association with adverse obstetric and prenatal outcomes is an emerging theme in health disparity research and is yet to be fully understood,” Eliner said in an interview. “Nonetheless, there is some evidence suggesting that racial/ethnic minorities with higher levels of education suffer from higher levels of stress.”
Implicit and explicit interpersonal bias and institutional racism may also play a role in the disparities, she said, and these factors may disproportionately affect the quality of care for more educated women. She also suggested that white women may be more comfortable advocating for their care.
“While less educated women from all racial/ethnic groups may lack the self-advocacy skills to discuss their labor course, educated white women may be more confident than women from educated minority groups,” Eliner told attendees. “They may therefore be better equipped to discuss the need for a cesarean delivery with their provider.”
Eliner elaborated on this: “Given the historical and current disparities of the health care system, women in racial/ethnic minorities may potentially be guarded in their interaction with medical professionals, with a reduced trust in the health care system, and may thus not feel empowered to advocate for themselves in this setting,” she said.
Allison Bryant Mantha, MD, MPH, vice chair for quality, equity, and safety in the OB-GYN department at Massachusetts General Hospital, Boston, suggested that bias and racism may play a role in this self-advocacy as well.
“I’m wondering if it might not be equally plausible that the advocacy might be met differently by who’s delivering the message,” Bryant Mantha said. “I think from the story of Susan Moore and patients who advocate for themselves, I think that we know there is probably some differential by who’s delivering the message.”
Finally, even though education is usually highly correlated with income and frequently used as a proxy for it, but the effect of education on income varies by race/ethnicity.
Since education alone is not sufficient to reduce these disparities, potential interventions should focus on increasing awareness of the disparities and the role of implicit bias, improving patients’ trust in the medical system, and training more doctors from underrepresented groups, Eliner said.
“I was also wondering about the overall patient choice,” said Sarahn M. Wheeler, MD, an assistant professor of OB-GYN at Duke University Medical Center in Durham, North Carolina, who comoderated the session with Bryant Mantha. “Did we have any understanding of differences in patient values systems that might go into some of these differences in findings as well? There are lots of interesting concepts to explore and that this abstract brings up.”
Eliner, Bryant Mantha , and Wheeler have disclosed no relevant financial relationships.