Fish Intake during Pregnancy and Risk of Low Birth Weight
Muthayya et al., European Journal of Clinical Nutrition . Advance online publication (2007).
Division of Nutrition, Maternal and Child Health Unit, St. John’s Research Institute, St. John’s National Academy of Health Sciences, Bangalore, India.
The long-chain omega-3 polyunsaturated fatty acids (DHA plus EPA) are known to play an important role during pregnancy via a structure-function role in the developing brain and central nervous system as well as having other apparent beneficial effects relating to gestation. The primary source of DHA plus EPA in a typical North American diet is fish wherein the amounts and types of omega-3 fatty acids vary across different species. The present study was initiated in India since this population consumes a diet which has a high cereal base and is accompanied by a very low consumption of DHA/EPA from fish. In addition, almost one third of babies born in India have low birth weights (LBW).
The present study was conducted on 676 women wherein their fish consumption was monitored throughout the three trimesters of pregnancy (including DHA plus EPA) and related to the risk of LBW. Interestingly, women who did not consume fish during the third trimester had a significantly greater risk of LBW (by 149% overall) as compared to those consuming an average of 9.3 g of fish per day. Furthermore, those in the highest tertile (33% of the population) with respect to long-chain omega-3 fatty acid intake (measured as EPA) had a 74% lower risk of LBW as compared to those with much lower intakes of EPA (from fish sources) in their diet. The authors conclude that low fish-eating pregnant women in India, particularly during the third trimester, is closely associated with a higher risk of LBW.
It is interesting to note that the total population as studied in these pregnant women from India has an average intake of DHA and EPA during the third trimester of pregnancy of only 11.0 and 3.0 mg, respectively. Such population intakes are dramatically lower than the intakes in North American women (82 and 35 mg, respectively, based on published reports); these latter intakes are themselves very low compared to intakes in many other countries. Those in the highest fish intake category in the present study from India averaged 9.3 g of fish per day which is the equivalent of only 1 fish serving (4 oz or 114 g) every 12 days. Further research and intervention trials wherein much higher intakes of fish than those reported herein and/or functional foods and/or supplements providing DHA plus EPA during pregnancy will be of considerable interest to determine a potential impact in reducing the high prevalence of LBW in Indian women.