Maternal supplementation with docosahexaenoic acid does not cause constriction of fetal ductus arteriosus: randomized controlled trial

Abstract

ObjectivesDocosahexaenoic acid (DHA) is routinely recommended to adequate fetal development during gestation. Since it is a substance with intense anti‐inflammatory action, its effects upon the fetal heart and circulation are unknown and safety of its administration during gestation is not yet established. This randomized clinical trial was designed to investigate if maternal supplementation of DHA is followed by alterations of maternal prostaglandin levels and fetal ductus arteriosus flow dynamics, at the final trimester of pregnancy.MethodsA double blind, placebo‐controlled, randomized clinical trial by parallel groups was designed. The study was developed in the period of 2018 to 2021. Pregnant women above 18 years of age, at 27 or 28 weeks without cardiac alterations at fetal echocardiography were enlisted to the trial, with exclusion of those taking substances with known prostaglandin inhibition effect, such as nonsteroidal anti‐inflammatory drugs and polyphenol‐rich foods. The intervention group received oral supplementation of omega‐3 with 450 mg/day of DHA, and the placebo group received capsules of soy lecithin. Both groups were supplemented for eight weeks. The following data were obtained at the beginning and at the end of the follow‐up: anthropometric, assessment of polyphenol and omega‐3 consumption, fetal morphological ultrasound, fetal Doppler echocardiographic examination and blood draw to assess prostaglandin levels. Participants were considered eligible, without cardiac or extracardiac abnormalities, when the diagnosis of ductal constriction was excluded by two observers. Intergroup and intragroup data were evaluated.ResultsThe study ended up with 24 participants in each group. After 8 weeks, Doppler echocardiographic parameters of ductal flow and serum prostaglandin levels in both groups did not show significant intergroup differences. The expected intragroup differences as a result in increase in gestational ages were present.ConclusionsEven though complete safety of DHA has not been tested, this randomized clinical trial shows that third trimester maternal supplementation of DHA, at the doses and period used, does not result in inhibition of PGE2 and does not cause ductus arteriosus constriction, providing the basis for post‐market surveillance studies with larger numbers, to allow the best clinical reassurance.This article is protected by copyright. All rights reserved.