Maternal DHA Supplementation

Objectives. Docosahexaenoic acid (DHA; 22:6 n-3) and arachidonicacid (AA; 20:4 n-6) are important for development of the centralnervous system in mammals. There is a growth spurt in the humanbrain during the last trimester of pregnancy and the first postnatalmonths, with a large increase in the cerebral content of AAand DHA. The fetus and the newborn infant depend on maternalsupply of DHA and AA. Our hypothesis was that maternal intakeof DHA during pregnancy and lactation is marginal and that highintake of this fatty acid would benefit the child. We examinedthe effect of supplementing pregnant and lactating women withvery-long-chain n-3 polyunsaturated fatty acids (PUFAs; codliver oil) on mental development of the children, compared withmaternal supplementation with long-chain n-6 PUFAs (corn oil).

Methods. The study was randomized and double-blinded. Pregnantwomen were recruited in week 18 of pregnancy to take 10 mL ofcod liver oil or corn oil until 3 months after delivery. Thecod liver oil contained 1183 mg/10 mL DHA, 803 mg/10 mL eicosapentaenoicacid (20:5 n-3), and a total of 2494 mg/10 mL

n-3 PUFAs. Thecorn oil contained 4747 mg/10 mL linoleic acid (18:2 n-6) and92 mg/10 mL

-linolenic acid (18:3 n-3). The amount of fat-solublevitamins was identical in the 2 oils (117 µg/mL vitaminA, 1 µg/mL vitamin D, and 1.4 mg/mL dl-

-tocopherol). Atotal of 590 pregnant women were recruited to the study, and341 mothers took part in the study until giving birth. All infantsof these women were scheduled for assessment of cognitive functionat 6 and 9 months of age, and 262 complied with the request.As part of the protocol, 135 subjects from this population wereinvited for intelligence testing with the Kaufman AssessmentBattery for Children (K-ABC) at 4 years of age. Of the 135 invitedchildren, 90 came for assessment. Six children did not completethe examination. The K-ABC is a measure of intelligence andachievement designed for children aged 2.5 years through 12.5years. This multi-subtest battery comprises 4 scales: SequentialProcessing, Simultaneous Processing, Achievement (not used inthe present study), and Nonverbal Abilities. The SequentialProcessing and Simultaneous Processing scales are hypothesizedto reflect the child’s style of problem solving and informationprocessing. Scores from these 2 scales are combined to forma Mental Processing Composite, which serves as the measure ofintelligence in the K-ABC.

Results. Childrenwho were born to mothers who had taken cod liver oil (n = 48)during pregnancy and lactation scored higher on the Mental ProcessingComposite of the K-ABC at 4 years of age as compared with childrenwhose mothers had taken corn oil (n = 36; 106.4 [7.4] vs. 102.3[11.3]). The Mental Processing Composite score correlated significantlywith head circumference at birth (r = 0.23), but no relationwas found with birth weight or gestational length. The children’smental processing scores at 4 years of age correlated significantlywith maternal intake of DHA and eicosapentaenoic acid duringpregnancy. In a multiple regression model, maternal intake ofDHA during pregnancy was the only variable of statistical significancefor the children’s mental processing scores at 4 yearsof age.

Conclusion. Maternal intake of very-long-chain n-3 PUFAs duringpregnancy and lactation may be favorable for later mental developmentof children.

Comment. We have known for some time now that DHA is important for mental and visual development in babies. We now learn that in-utero supplementation is probably important also (especially in American women whose diet is relatively deficient in DHA. The next step should be adding DHA supplements to prenatal vitamins. Compliance with this form of supplementation would have to be better than asking pregnant women to take cod liver oil every day (yuk!). ABK

Maternal Supplementation With Very-Long-Chain n-3 Fatty Acids During Pregnancy and Lactation Augments Children’s IQ at 4 Years of Age. Helland IB, Smith L, Saarem K, et al. PEDIATRICS (January 2003); 111:e39-e44.