There’s nothing fishy about it: DHA (or docosahexaenoic acid), an omega-3 fatty acid found in fish oil, is an essential nutrient for women — especially during pregnancy. Many studies have found that DHA supplements during pregnancy seem to offer a developmental advantage later in childhood as well. Because of the fat’s vital role in brain development, experts recommend that pregnant women get 300 milligrams (mg) of DHA each day. Women can get this quota of DHA per day by eating a couple tuna fish sandwiches, plus a serving of fatty fish like salmon, each week. Other sources of DHA include fish oil pills and algae-derived DHA, which is included in some prenatal vitamins. Pregnant and breastfeeding women should, however, avoid certain fatty fish, because they could have high mercury levels. These include shark, swordfish, king mackerel and tilefish.
Adults need to get DHA from food, and a baby in utero needs to get these fats from its mother. Newborns get DHA from breast milk or from baby formula supplemented with DHA. It’s so important that even if a mother doesn’t consume much DHA, her body will use its own reservoir of DHA to provide it to her growing baby during gestation and then through breast milk after birth.
Current research suggests adequate levels of DHA may help increase a developing baby’s cognitive functioning, reduce the risk of pre-term labor and decrease the risk of postpartum depression.
Benefits of DHA for growing babies include:
Brain development. In a study of 98 pregnant women, researchers at the School of Pediatrics and Child Health at the University of Western Australia found that two years after birth, the children whose mother had received a high dose of fish oil (including 2.2 g of DHA) in the second half of their pregnancy had higher scores in tests of their eye-hand coordination. Another study, from the University of Oslo in Norway, found that four-year-olds scored better on IQ tests if their mothers took DHA supplements during pregnancy and breastfeeding.
Visual development. A study of 167 pregnant women conducted at the University of British Columbia’s Department of Pediatrics suggested a correlation between visual acuity in two-month-old babies and their mother’s DHA intake during their second and third trimesters of pregnancy.
Higher birth weight. Researchers at Maastricht University in the Netherlands studied 782 mother-baby pairs and found “significant positive associations” between the mother’s DHA levels (especially early in pregnancy) and the baby’s weight and head circumference at birth.
Risk of preterm labour. In a trial of women receiving DHA supplementation during the third trimester, the average length of gestation increased six days (Obstetrics & Gynecology, 2003).
Postpartum Depression. Research has found low levels of DHA in mother’s milk and in the red blood cells of women with postpartum depression. (Journal of Affective Disorders, 2002). Some scientists believe increasing levels of maternal DHA may reduce the risk of postpartum depression.
Re Renowned figures speak out about DHA
Research findings such as these have led pregnancy and child health experts to spread the word about the importance of DHA during pregnancy. Dr. William Sears, one of the nation’s leading experts on child health and development and longtime advocate of DHA, states “DHA is the most important brain-building nutrient at all ages, especially during pregnancy and the pre-school years when the child’s brain is growing the fastest.” In what many consider the modern day pregnancy bible, What to Expect When You are Expecting, Heidi Murkoff, et.al., devotes a section to the importance of adequate DHA in the pregnancy diet chapter of her book. She explains that DHA is important during pregnancy, “especially during the last three months, when your baby’s brain grows at a rapid pace and lactation (the DHA content of a baby’s brain triples during the first three months of life).” Another maternity expert, Rebecca Matthias, president of Mothers Work, Inc., the nation’s leading maternity retailer touts the benefits of DHA in her latest book, 51 Secrets of Motherhood. She celebrates DHA as “the new wonder supplement that actually increases your baby’s growth.”
How much DHA do you need?
While there are not yet official recommendations on the amount of DHA pregnant women need, a recent review of research published by the Journal of Perinatal Medicine concluded that pregnant and lactating women need 200 mg of DHA a day; Johnson suggests the same amount.
Sources of DHA
So where can pregnant women get that daily dose of DHA? “Food is best,” says Johnson, “so if a woman can, she should start there. Salmon, canned light tuna, and products with added DHA such as eggs and milk are all good options, as are anchovies, herring, sardines, walnuts, and walnut oil. If you’d rather take a DHA supplement, go for one derived from algae rather than fish oil — it’ll be gentler on your stomach. (Then you’ll be getting your DHA just as the fish do; their source is marine algae.)
Eating Fish Safely
Fish is a fantastic source of DHA, but pregnant and breastfeeding women need to exercise caution. You want to eat enough oily, fatty fish to reap the DHA benefits but not enough to add too much dangerous mercury to your diet (and your baby’s). Remember these guidelines:
Shark, swordfish, king mackerel, fresh tuna, tilefish, mahi-mahi, grouper, amberjack, and fish from contaminated waters
Eat sparingly (6 oz. or less per week)
Canned (or packaged) albacore tuna and freshwater fish caught by family and friends
Eat carefully (up to 12 oz. per week)
Shellfish, canned (or packaged) light tuna, smaller ocean fish, farm-raised fish, and store-bought freshwater fish
Salmon (opt for wild or organically farmed), sea bass, sole, flounder, haddock, halibut, ocean perch, pollack, cod, and trout