To come to this conclusion, researchers first measured docosahexaenoic acid (DHA) concentration--a type of omega-3 fatty acid involved in the development of neurons and retinas--in the umbilical cord blood of 109 infants. "DHA concentration in the umbilical cord is a good indicator of intra-uterine exposure to omega-3s during the last trimester of pregnancy, a crucial period for the development of retinal photoreceptors and neurons," explains Dr. Dewailly.

Tests conducted on these infants at 6 and 11 months revealed that their visual acuity as well as their cognitive and motor development were closely linked to DHA concentration in the umbilical cord blood at the time of their birth. However, there was very little relation between test results and DHA concentration in a mother's milk among infants who were breast-fed. "These results highlight the crucial importance of prenatal exposure to omega-3s in a child's development," points out Dr. Muckle.

Researchers observed that DHA concentration in the umbilical cord blood was in direct relation with the concentration found in a mother's blood, a reminder of the importance of a mother's diet in providing omega-3 fatty acids for the fetus. They also noted that DHA concentration was higher in the fetus's blood than in the mother's. "While developing its nervous system, a fetus needs great quantities of DHA. It can even transform other types of omega-3s into DHA in order to develop its brain," explains Dr. Dewailly.

For the members of the research team, there is no doubt that all pregnant women should be encouraged to get sufficient amounts of omega-3s. "A diet rich in omega-3s during pregnancy can't be expected to solve everything, but our results show that such a diet has positive effects on a child's sensory, cognitive, and motor development. Benefits from eating fish with low contaminant levels and high omega-3 contents, such as trout, salmon, and sardines, far outweigh potential risks even during pregnancy," conclude the researchers.

In addition to Muckle and Dewailly, who are also affiliated to the Centre de recherche du CHUQ, Quebec City, the study was co-authored by Pierre Ayotte from Université Laval, as well as Joseph Jacobson, Sandra Jacobson, and Melissa Kaplan-Estrin from Wayne State University. This study was funded by the National Institute of Environmental Health Sciences, Indian and Northern Affairs Canada, Hydro-Québec, and Health Canada.

Note: If no author is given, the source is cited instead.

• Pregnancy and Childbirth
• Cholesterol
• Nutrition

• Child Development
• Intelligence
• Neuroscience

• Oily fish
• Stillbirth
• Placenta
• Umbilical cord
• Sensory neuron
• Omega-3 fatty acid