Nutrition plays one of the most important roles in a healthy pregnancy, and many studies have linked the consumption of omega-3-rich fish and fish products to improved brain health. Now, a new study published in the American Journal of Epidemiology has found consumption of three sizeable servings of fish each week during pregnancy may present moderate child neuropsychological benefits, including improvements in cognitive functioning and some protection from autism-spectrum traits.
Researchers at the Center for Research in Environmental Epidemiology in Barcelona analyzed data from the Spanish Childhood and Environment Project between 2004 and 2008. Nearly 2,000 Spanish mother-child pairs were followed from the first trimester of pregnancy through the child’s fifth birthday. Researchers focused on records of the women’s consumption of large fatty fish such as swordfish and albacore tuna, smaller fatty fish such as mackerel, sardines, anchovies or salmon, and lean fish such as hake or sole, as well as shellfish and other seafood.
Women were tested for blood levels of vitamin D and iodine, and cord blood was tested after delivery to measure fetal exposure to mercury and PCB pollutants. At ages 14 months and 5 years, the children underwent tests of their cognitive abilities and Asperger Syndrome traits to assess their neuropsychological development.
On average, the women had consumed about 500 g, or three servings, of seafood per week while pregnant; however, with every additional 10 g per week above that amount (up to 600 g), children’s test scores improved. The link between higher maternal consumption and better brain development in children was especially apparent when kids were 5 years old. They also saw a consistent reduction in autism-spectrum traits with increased maternal fish consumption.
Even when women averaged 600 grams of fish weekly during pregnancy, there was no sign that mercury or other pollutants associated with fish were having a negative effect that offset the apparent benefits, the researchers concluded. There was no additional benefit when women ate more than 600 g of fish per week.
In 2014, FDA recommended pregnant women eat at least 8 ounces and up to 12 ounces (2 to 3 servings) per week of a variety of fish that are lower in mercury to support fetal growth and development.
For more information about nutrition during pregnancy, download the Nutritional Requirements During Pregnancy Slide Show that explains the changes a body goes through during pregnancy, as well as the nutritional needs to ensure a healthy pregnancy.
