Study results show 25% of pregnant people are not getting enough omega-3 fatty acids from their diet or dietary supplements

Results from a new nationwide cohort study show that, despite strong recommendations in favor of consuming omega-3 fatty acids for optimal pregnancy outcomes and offspring health, 25% of participants reported rarely, or never eating fish during pregnancy, with fewer taking omega-3 supplements.

The study, “Demographic and health characteristics associated with fish and n-3 fatty acid supplement intake during pregnancy: results from pregnancy cohorts in the ECHO program” was led by investigators at the Harvard Pilgrim Health Care Institute and published February 27 in Public Health Nutrition. The study is timely, arriving as the World Health Organization and U.S. National Academies both plan to issue reports on the risks and benefits of fish consumption in pregnancy later this year.

“Omega-3 fatty acids are essential nutrients for supporting positive health outcomes. Getting enough of these nutrients during pregnancy is vital for preventing preterm birth and promoting optimal child health and neurodevelopment,” said the study’s lead author Emily Oken, Harvard Medical School professor and chair of the Department of Population Medicine at the Harvard Pilgrim Health Care Institute.

Prior research looking at the demographic characteristics associated with fish and supplement intake during pregnancy has been limited, involving fewer participants and older data that may not represent current intake. The study team addressed this research gap using information on fish consumption reported by 10,800 pregnant women, and supplement intake information from 12,646 pregnant women from cohorts across the U.S. participating in the Environmental influences on Child Health Outcomes (ECHO) program.

Study results showed that nearly 25% of participants reported not eating fish or eating it less than once per month, and only 16% took supplements. Contrary to expectations, supplement use was less common among those who consumed less fish, putting that group at even higher risk for insufficient omega-3 fatty acid intake.  Similar to supplement use, older participants with a higher income and education consumed more fish. However, unlike supplements, fish consumption was higher in those with racial/ethnic identities other than non-Hispanic White and in those who used tobacco and nicotine products. The highest likelihood of supplement intake was among those who were older, had a higher education and income, and were non-Hispanic White or Asian. Additionally, supplement use was less common among those at higher risk for adverse pregnancy outcomes as a function of using tobacco or nicotine products or having a higher BMI.

“Current evidence shows that the benefits of maternal consumption of low-mercury fish, or in its place, omega-3 supplements, outweigh any potential  risks,” says Dr. Oken. “Our study provides updated information to inform much needed public health advice and resources to support clinical conversations to encourage consumption of low-mercury fish during pregnancy and intake of omega-3 supplements among those who do not consume fish.”