PORTLAND, OREGON. Animal experiments have shown that monkeys born by mothers with low blood levels of docosahexaenoic acid (DHA) develop impaired vision. There is also evidence that premature human infants fed standard infant formulas (very low in DHA) have impaired visual function which can be improved significantly by adding fish oils to their formulas. All this adds to the growing evidence that DHA is essential for the proper development of the brain and retina in the fetus and infant.
Researchers at the Oregon Health Sciences University recently set out to answer the question "Do high intakes of DHA by pregnant women increase the DHA level in their newborn infants?" Their clinical trial involved 31 healthy, pregnant women 15 of whom were assigned to receive 2.6 grams/day of omega-3 fatty acid from fish (1.01 grams DHA/day) from their 26th to their 35th week of pregnancy. The remaining women served as controls. The fish oil supplement was taken as a combination of tinned sardines and fish oil capsules; either 1 half tin of sardines plus 7 fish oil capsules per day, 1 tin of sardines (3 3/4 oz) plus 3 fish oil capsules per day or 10 fish oil capsules (10 grams) per day. Blood samples were collected from mothers at entry to the study, monthly after entry and at delivery, and from the infants at delivery. The level of DHA in the red blood cells of supplemented mothers rose from 4.69% (of total fatty acids) at entry to 7.15% at the end of week 34 and then declined (as expected) to 5.97% at delivery. DHA increases in the blood plasma paralleled the increase in the red blood cells, but at a lower level. DHA levels in newborn infants differed greatly depending on whether the mothers had supplemented or not. Red blood cell levels in infants born by supplementing mothers were 35.2% higher than in the control infants and blood plasma levels were 45.5% higher (5.05% vs. 3.47%).
The researchers believe that supplementing pregnant mothers with fish oil may benefit brain and retinal development in their offspring particularly if born prematurely. They point out that supplementing from mid-pregnancy to the 34th week is perfectly safe and may reduce the incidence of preeclampsia (pregnancy-related high blood pressure) as well.
Connor, William E., et al. Increased docosahexaenoic acid levels in human newborn infants by administration of sardines and fish oil during pregnancy. Lipids, Vol. 31 (suppl), 1996, pp. S183- S87