How Much DHA Do Expecting Mothers Need To Support A Healthy Pregnancy?

Good nutrition is crucial at every point in your life, but it's especially vital when you're pregnant. After all, you're taking in nutrients for both you and baby. 

If you're taking a prenatal multivitamin or want to complement your prenatal vitamin with some healthy omega-3s, it's a really good idea to see if it contains a solid amount (more on that later) of docosahexaenoic acid (DHA). This marine-derived omega-3 fatty acid has been linked to healthy fetal growth and development1, along with a slew of other perks for you and your growing baby.* 

DHA is one of the main and most well-researched types of omega-3 fatty acids. Omega-3s are found in certain foods (like flaxseed and fatty fish), along with dietary supplements (like fish oil or algal oil). There are several types of omega-3 fatty acids, but the most widely studied include EPA (eicosapentaenoic acid), DHA, and ALA (alpha-linolenic acid).

While some biological properties overlap (i.e., they all have antioxidant and anti-inflammatory actions), each of these omega-3 fatty acids also has its own unique and powerhouse roles in the body. 

In general, ALA is found in plant-based foods, while fatty fish, the algae they consume, and shellfish (e.g., oysters, mussels, lobsters, and crab) are the best sources of EPA and DHA.

"DHA helps with fetal growth and development,"* says Lisa R. Young, Ph.D., RDN, CDN, registered dietitian nutritionist and adjunct professor of nutrition at New York University. The nutrient has also been linked with cognitive function, proper blood flow, hydrated skin, cardiovascular health, optimal eye health, and more.*

Since your body can't make a lot of DHA, getting enough from your diet and high-quality supplementation is critical during pregnancy, says Christine Greves, M.D., a board-certified OB/GYN at the Winnie Palmer Hospital for Women & Babies. 

Greves calls DHA "the most important type of fat in pregnancy," thanks to its critical involvement in so many different parts of the body. Perhaps most well known is DHA's reputation as a key proponent of fetal brain development in the womb3 (and after birth, i.e., the postnatal period).* 

Whether nine months or 99 years old, the omega-3 fatty acid makes up a large majority of the gray matter in the brain, which controls everything from memory and emotions to movement. Additionally, DHA helps protect and maintain the structural integrity of cell membranes and neurons (which are responsible for sending and receiving messages throughout the central nervous system).* 

DHA is also important for fetal eye development4 and visual functioning.* "During pregnancy, DHA, in particular, helps with the development of the baby's brain and eyes,"* Young explains.

Observational studies have also linked higher intake of DHA from fish during pregnancy to better infant health outcomes.* In an American Journal of Epidemiology prospective cohort study of 341 mother-child pairs in the U.S., researchers found moms who had fish more than twice a week had babies with better visual-motor skills at age 35 compared to their counterparts with lower fish intake.

Another observational cohort study6 in the U.K. published by the Lancet analyzed data from 11,875 pregnant women with seafood intakes ranging from none to approximately 12 ounces per week. Researchers discovered that children of mothers who consumed less seafood during pregnancy were more likely to have suboptimal communication skills, verbal IQ, and prosocial behavior.

This is a little complicated. Currently, there's an established daily nutritional requirement for ALA, per the National Academies’ Food and Nutrition Board: 1,100 milligrams per day for adult women and 1,600 milligrams for adult men. (To put that number into perspective, a serving of walnuts has 2,600 milligrams of ALA7.)

Technically, there's no established recommendation for DHA dosage, although as nutrition scientist Ashley Jordan Ferira, Ph.D., RDN, explains, "The desire for EPA and DHA to be assigned their own established dietary reference intakes8 by the National Academies has been a desire that researchers, doctors, and nutritionists alike have shared for many years."

Ferira goes on to say that, "while we wait on that recommendation to be issued, we can share what the science and clinical consensus say." Speaking of clinical consensus, doctors generally recommend9 that pregnant individuals consume 200 milligrams of DHA a day, says Greves. You can find DHA in certain prenatal multivitamins or as a separate, stand-alone omega-3 supplement, too.

On the food front, The American College of Obstetricians and Gynecologists (ACOG) recommends that people eat at least two servings (i.e., eight to 12 ounces) of fish or shellfish a week for their EPA and DHA content before getting pregnant, while pregnant, and while breastfeeding. 

Unfortunately, it's common to have a DHA insufficiency. "Most Americans don't eat enough fish to meet their needs for omega-3s and DHA, so insufficiency is pretty common," Cording says. Evidence indicates that up to 90% of Americans12 aren't getting enough DHA.

You can also get DHA from algae and a small amount from eggs enriched with omega-3s, Young points out. 

While it's possible to get your DHA from eating fish, Cording points out that most Americans don't—and that's where supplementation comes in. "I encourage people to take an omega-3 supplement," she says. "In pregnancy, your needs are higher, and it's hard to cover them through food."

What's more, "during pregnancy, you're extra cognizant of contaminants like heavy metals and other toxins found in fish and elsewhere, so the case for a purified omega-3 supplement source of DHA becomes even more compelling," adds Ferira.