DHA intake of US adults is low and conversion of ?-linolenic acid (18:3n-3) to DHA (22:6n-3) is also low. As a result US women enter pregnancy with lower DHA status than other countries in the developed world suggesting a potential deficiency of an important nutrient that has been shown to reduce inflammation. The goal of this Phase III Clinical Trial (randomized, double-blind, and placebo-controlled) is to test the primary hypothesis that supplementing US women with 1000 mg of docosahexaenoic acid (DHA), 800 mg above the amount currently in many prenatal nutritional supplements (~200 mg) during the half of pregnancy can reduce early preterm birth (ePTB) (<34 wk. gestation). This was a favorable secondary outcomes of a US trial (RO1 HD047315, Clinical Trials.gov ID: NCT00266825) conducted at one of the proposed study sites on which the current proposal is modeled. Secondary outcomes include birth weight <1500g and pregnancy outcomes (preeclampsia, gestational diabetes, C-section delivery). We propose a Bayesian Adaptive Design with 90% power to detect the hypothesized outcomes with an estimated 938 subjects that allows the study to stop early if strong results (probability >0.995) are observed before the study is scheduled to end and places 60% of the participants on the better DHA dose. Conventional equal randomization with 90% power would require 1200 subjects, be longer, and place only 50% of the participants on the better DHA dose. The proposed study has the potential to determine if nutritional supplementation with DHA during pregnancy can reduce the incidence of ePTB, a serious public health problem with large societal and family costs. The randomization design has the potential to significantly expedite findings to the research community and clinical practice.

Public Health Relevance

DHA is a nutrient that is low in the diet of US women. Early preterm birth (ePTB), i.e., birth before 34 weeks gestation, affects 3.4% of US pregnancies and results in births with the highest overall infant mortality and morbidity. The current project seek to determine if prenatal nutritional supplementation with 1000 mg per day of docosahexaneoic acid (DHA) can reduce early preterm birth (birth before 34 wk gestation). A positive finding would have enormous implications for the formulation of public policy on prenatal nutrition.

National Institute of Health (NIH)
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Research Project (R01)
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Special Emphasis Panel (ZRG1)
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Miodovnik, Menachem
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University of Kansas
Sch Allied Health Professions
Kansas City
United States
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Carlson, Susan E; Gajewski, Byron J; Valentine, Christina J et al. (2017) Assessment of DHA on reducing early preterm birth: the ADORE randomized controlled trial protocol. BMC Pregnancy Childbirth 17:62