23 Jan 2019 --- An omega 3 DHA target blood level of 5 percent or higher reduces the risk of preterm birth, according to a new study. Previous studies had uncovered that DHA levels in pregnant women are often low and researchers support that there continues to be inadequate intake of the fatty acid despite strong recommendations. The study, published in the December edition of Nutrients, discusses the ramifications of DHA depletion in pregnant women and sets a clear target level.