Consumption of DHA omega-3 fatty acid (docosahexaenoic acid) during pregnancy and breastfeeding is normally associated with healthy pregnancies as well as right mental and visual development of infants.
A study published in American Journal of Clinical Nutrition showed the effect of DHA supplementation during pregnancy on the problem solving ability of the infants during the first year of life. 29 pregnant women were recruited at gestation week 24 and randomly assigned them to receive either a daily DHA-cereal bar (300 mg DHA) or placebo-cereal bar. When the infants had nine months of age, they were tested using The Infant Planning Test and Fagan Test of Infant Intelligence. Children of mothers supplemented with DHA-functional food had significantly better performance for problem-solving.
Other study published in the same scientific journal presented evidence of a beneficial effect of daily prenatal DHA supplementation on objective measures of attention and executive function at preschool age. This study included 1.094 Mexican women randomly assigned to receive DHA or placebo during their last 22 weeks of pregnancy. Then researchers were able to assess data from 797 of the children at age five. Results showed a significant improvement in attention in children from mother consuming DHA versus placebo.
References: Am. J. Clin. Nutr. (2007) 85, 1572-1577
Am. J. Clin. Nutr. (2016) 104, 1075-1082