UC Irvine Study Finds Health Insurance Coverage Gaps Limit Folic Acid Use, Increasing Birth Defect Risks
核心洞察
A UC Irvine study analyzing data from over 85,000 women found that lack of health insurance significantly reduces the likelihood of folic acid supplementation among women of reproductive age.
Folic acid is critical for preventing neural tube defects (搜索) such as spina bifida (搜索) and anencephaly (搜索), which develop early in pregnancy before many women know they are pregnant.
Among Hispanic women, factors such as age, pregnancy status, education, and insurance coverage—rather than birthplace—were associated with supplement use.
A new study from the University of California, Irvine has revealed that access to healthcare and health insurance coverage strongly determines whether women of reproductive age take recommended amounts of folic acid, a vitamin B form critical for preventing serious birth defects. The research, published in the Journal of Sexual and Reproductive Healthcare, analyzed health data from more than 85,000 women ages 18 to 49 across the United States using the National Institutes of Health's All of Us Research Program.
The findings underscore a persistent public health challenge: despite long-standing national guidelines recommending daily folic acid for women who could become pregnant, overall use remains low—and structural barriers, rather than personal choice alone, appear to be a primary driver.
The Role of Folic Acid in Preventing Neural Tube Defects (搜索)
Folic acid helps prevent neural tube defects (搜索) such as spina bifida (搜索) and anencephaly (搜索), conditions that develop very early in pregnancy, often before a woman knows she is pregnant. This biological reality is why health experts recommend daily supplementation for all women of reproductive age, not only those actively planning pregnancy.
Yet the UC Irvine team found that women without health insurance were significantly less likely to report taking folic acid supplements. Older pregnant women, by contrast, were more likely to use supplements—a trend researchers said may reflect greater access to healthcare providers and prenatal care services.
"Preventing neural tube defects (搜索) begins long before pregnancy, which is why access to healthcare and preventive education is so important for all women of reproductive age," said corresponding author Yael Marks, health sciences assistant clinical professor in the UC Irvine School of Pharmacy & Pharmaceutical Sciences. "Our findings show that structural barriers like insurance coverage can strongly influence whether women receive this simple but lifesaving intervention."
Racial and Ethnic Patterns in Supplement Use
The study also examined racial and ethnic differences in folic acid consumption. Notably, non-Hispanic Black women were more likely than non-Hispanic White women to report taking folic acid supplements. Among Hispanic participants, researchers found no significant difference between U.S.-born and foreign-born women. Instead, age, being pregnant, educational attainment, and health insurance coverage were the factors most strongly associated with supplementation within this group.
These results challenge assumptions that birthplace alone determines preventive health behaviors, instead highlighting the influence of broader social and economic conditions.
"This collaboration allowed us to examine folic acid supplementation not only as a medical issue, but also through the lens of social inequities and healthcare access," said co-author Isabel Almeida of the Department of Chicano/Latino Studies and Department of Psychology. "Bringing together researchers from different disciplines helps us better understand the barriers communities face and identify more effective public health solutions."
Policy Implications and Fortification Efforts
The study's findings arrive at a pivotal moment for public health policy. In January 2026, California became the first state to require folic acid fortification of corn masa flour products, including tortillas, a measure designed to reduce neural tube defects (搜索) among populations that consume masa-based foods as dietary staples. The UC Irvine research also supports broader efforts to expand folic acid fortification in corn masa flour and tortillas in other states—foods commonly consumed in many Hispanic households.
The project brought together researchers across multiple UC Irvine disciplines, including the School of Pharmacy & Pharmaceutical Sciences, the Department of Chicano/Latino Studies, and the Department of Psychology, reflecting the value of cross-divisional collaboration in addressing public health disparities.
The All of Us Research Program, funded by the National Institutes of Health, aims to enroll at least 1 million participants from diverse backgrounds to advance personalized medicine and public health research. UC Irvine serves as a host site for the program, with collaborations spanning the School of Medicine, the Genetic Epidemiology Research Institute, and other campus partners.
Additional authors of the study include Brian Vu and Tara Mostafazadeh of the Department of Clinical Pharmacy Practice at UC Irvine.