Efficacy of Omega-3 PUFAs on Depressive Symptoms among Expectant Mothers: Collaborative Trials in Japan and Taiwan

Dr. Daisuke Nishi  d-nishi@umin.ac.jp



Safe strategies for managing depression in pregnancy are needed, and the possible efficacy of omega-3 polyunsaturated fatty acids (PUFAs) for depression has been suggested. However, evidence has not been well established especially in Japan, where fish consumption is higher than almost any other countries.


A 12-week, prospective, open-label pilot trial in pregnant women with depressive symptoms was conducted in Japan and Taiwan, using supplements containing 1.8 g omega-3 PUFAs (1.2 g EPA and 0.6 g DHA). Pregnant women between 12 to 24 weeks’ gestation with Edinburgh Postnatal Depression Scale scores of ≥9 were recruited in Japan and Taiwan. The primary outcome measure was change in total score on the 17-item Hamilton Rating Scale for Depression (HAMD) during the supplementation.


Of the 13 participants, 9 completed the trial. Omega-3 PUFAs supplementation was well tolerated, and a significant decrease in HAMD score was observed after 12 weeks of supplementation (mean, 4.8; standard deviation, 4.9) compared with baseline (mean, 12.1; standard deviation, 3.7) (paired t-test; p < 0.01). The decrease in HAMD score from baseline to 12 weeks after the start of the intervention was significantly larger in Japanese participants than in Taiwanese participants (Wilcoxon rank sum test; p = 0.045).


The findings suggested potential efficacy of moderate omega-3 PUFAs for improving depressive symptoms in Japan and Taiwan. Then we have conducted a multicenter, double-blind, parallel group, randomized controlled trial to determine the efficacy of omega-3 PUFAs in two countries.