ECHO Study Suggests Most Prenatal Vitamins May Not Provide All of the Nutrients Pregnant People Need

Authors: Katherine Sauder, et al.

Who sponsored this study?

This research was supported by the Environmental influences on Child Health Outcomes (ECHO) Program, Office of The Director, National Institutes of Health.

What were the study results?

Out of all the prenatal supplements analyzed, the study found one that may potentially give pregnant patients the optimal amounts of the most important nutrients. But, the monthly cost of this supplement can be too high for some people, and it requires pregnant people to take seven pills a day. To ensure that pregnant people have accessible options for prenatal vitamins, the researchers looked for dietary supplements containing close to the needed amounts of nutrients that cost less and required only one to two pills a day.

See the full publication (Appendix A) for a list of the prenatal supplements analyzed during this study and their nutritional contents.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What was the study's impact?

This study can inform pregnant people and their doctors about key nutrients they may be missing in their diet and what prenatal vitamins they can take to get those nutrients. Companies that manufacture prenatal vitamins can also use the results of this study to understand how much of these nutrients should be in the products they make. Importantly, this study highlights the ongoing need for more prenatal vitamin options that are low cost and convenient, while still containing the optimal amounts of key nutrients.

Why was the study needed?

It is important that pregnant people get the right amounts of the nutrients they need for a healthy pregnancy. There are thousands of options for prenatal dietary supplements in the United States, so ECHO researchers conducted this study to help pregnant people and doctors pick the ones that contain optimal doses of key micronutrients to support a healthy pregnancy.

Who was involved?

This study included 2,450 pregnant participants from six ECHO cohorts located across the United States.

What happened during the study?

ECHO researchers first analyzed data about what the participants ate and drank during their pregnancies. Then, they calculated how much vitamin A, vitamin D, folic acid, calcium, iron, and omega-3 fatty acids the pregnant participants were getting from their diet. The researchers compared the participants’ diets to nutrition recommendations for pregnancy to determine the amount of nutrients the participants would need from a prenatal vitamin to make up what they were missing in their diet.

The researchers compared over 20,000 prenatal vitamins available in the US, focusing on the nutrients that are most important for maternal and infant health: vitamin A, vitamin D, folic acid, calcium, iron, and omega-3 fatty acids.

What happens next?

In addition to the use of prenatal dietary supplements, pregnant people can adjust their diet to include more of the nutrients they need for a healthy pregnancy. Going forward, more research is needed to identify foods that pregnant people could eat to get enough of these nutrients.

Where can I learn more?

Access the full journal article, titled “Selecting a dietary supplement with appropriate dosing for six key nutrients in pregnancy" in The American Journal of Clinical Nutrition.

Read more information about healthy eating during pregnancy on the American College of Obstetricians and Gynecologists website.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published April 2023

Access the associated article.