Effect of omega-3 fatty acids on premenstrual syndrome: A systematic review and meta-analysis

To date, no definitive results have been reported on the effect of omega-3 fatty acids on premenstrual syndrome (PMS). Therefore, this systematic review and meta-analysis aimed to determine the effect of omega-3 fatty acids on PMS.

In this systematic review and meta-analysis, the databases were searched. In this regard, randomized clinical trials investigating the effect of omega-3 fatty acids on PMS were included. The quality of the studies was assessed using the Cochrane Collaboration's Risk of Bias tool. Meta-analysis was done based on random effects model and calculation of standardized mean difference (SMDs).

The results of meta-analysis showed that omega-3 fatty acids were efficient in reducing the severity of PMS in women (SMD = -0.968, 95% confidence interval [CI]: -1.471 to -0.464). In addition, the results showed that the studies were heterogeneous (I²  = 89.11%, p <0.001). Based on meta-regression analysis, aging (β = -0.150, 95% CI -0.202 to -0.098, p <0.001) and increasing the duration of intervention (β = -0.579, 95% CI -0.781 to -0.378, p <0.001) had a significant effect on the severity of PMS. We also found that omega-3 fatty acids could significantly reduce the somatic (SMD = -0.800, 95% CI: -1.126 to -0.474) and psychological (SMD = -0.373, 95% CI: -0.686 to -0.061) symptoms of PMS.

Omega-3 fatty acids could reduce the severity of PMS. However, we should caution in the conclusion in affirming the beneficial effects of n-3 PUFAs on PMS, since the heterogeneity is evident in the analysis. The efficacy of the treatment was enhanced by increase of the treatment duration.