Do Omega-3 Fatty Acids Prevent Depression in Pregnant Women?

Fish oil supplementation that is rich in omega-3 fatty acids does not prevent depressive symptoms during pregnancy or in the postpartum period, according to the results of a double-blind, randomized controlled trial.¹
   
The relative safety and additional health benefits of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) has led to growing interest in their use during pregnancy as preventive or therapeutic modalities for depression. However, the results of previously published trials have disagreed about the beneficial effects of these supplements for perinatal depression. To help clarify previous findings, the study authors tested the effects of fish oil containing either EPA or DHA on the prevention of depressive symptoms among pregnant women at increased risk for depression. According to the study authors, this is the first study comparing EPA and DHA fish oils in pregnant women.¹
   
There were 126 pregnant women enrolled in the study, all with either a history of depression or a score of 9 to 19 on the Edinburgh Postnatal Depression Scale. Eight women dropped out of the study, leaving 39 women randomized to EPA-rich fish oil, 38 women randomized to DHA-rich fish oil, and 41 women randomized to placebo. All participants completed the Beck Depression Inventory (BDI) and Mini-International Neuropsychiatric Interview at enrollment, 26 to 28 weeks’ gestation, 34 to 36 weeks’ gestation, and 6 to 8 weeks’ postpartum. Serum fatty acid levels were recorded at entry and at 34 to 36 weeks’ gestation.
   
There were no differences between study groups in the change in BDI scores from study entry to any of the 3 reassessment periods after supplementation. Although the EPA-rich and DHA-rich fish oil groups had significantly increased concentrations of serum EPA and serum DHA, respectively, after supplementation, the use of these fish oils during pregnancy did not prevent depressive symptoms in pregnant women at risk for depression. However, women who used DHA-rich fish oil had a significantly longer pregnancy (40.4 weeks) compared with women who used EPA-rich fish oil (39.1 weeks) and placebo (39.1 weeks). In addition, serum DHA concentrations at 34 to 36 weeks’ gestation were inversely related to BDI scores in late pregnancy.
   
The study authors suggested that although omega-3 fatty acids do not prevent depressive symptoms in pregnant women at risk for depression, these supplements effectively treat perinatal depression. Additional research is needed to better understand how serum DHA concentrations affect depressive symptoms.

Pertinent Points:
- Use of omega-3 fatty acid supplements in pregnant women at increased risk for depression does not prevent depressive symptoms during pregnancy.
- The use of DHA-rich fish oil significantly prolonged the pregnancy and increased birth weight.
 

References:

1. Mozurkewich EL, Clinton CM, Chilimigras JL, et al. The Mothers, Omega-3, and Mental Health Study: a double-blind, randomized controlled trial. Am J Obstet Gynecol. 2013;208:313.e1-9.