Polyunsaturated fatty acids and inflammatory markers in major depressive episodes during pregnancy

Introduction: Prenatal depression (PND) is a common psychiatric disorder in pregnant women and leads to psychosocial dysfunction, high suicidal rate, and adverse childcare. Patients with PND have omega-3 polyunsaturated fatty acid (omega-3 or n-3 PUFAs) deficits, which might link to chronic low-grade inflammatory process and the pathophysiological mechanisms of depression. In this case-control study, we examined the levels of PUFAs and inflammatory cytokines in PND. Method: Blood samples were obtained and analyzed from 16 healthy controls and 17 depressed cases (PND group) diagnosed with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Independent sample t-test and correlation analysis were performed with Statistical Package for the Social Sciences (SPSS) logistics correlation analysis. Results: PND group had significantly lower levels of total n-3 (p = 0.026), docosahexaenoic acid (DHA) (p = 0.020) and eicosapentaenoic (EPA) (p = 0.019) but a higher omega-6 (n-6)/n-3 PUFAs ratio (p = 0.007) and tumor necrosis factor alpha (TNF-α) (p = 0.016) level. Moreover, the duration of current PND episodes were also significantly correlated with DHA, EPA, n-3 PUFAs, n-6/n-3 ratio and TNF-α. In terms of PUFAs and cytokine levels, only DHA was inversely correlated with TNF-α. Conclusion: PND is significantly associated with lower DHA, EPA, and total n-3 PUFAs levels and an increased n-6/n-3 PUFAs ratio, while the duration of PND is associated with lower levels of n-3 PUFAs, including DHA and EPA. The correlation of PUFAs levels with depression and TNF-α level grant further investigation into the inflammatory process underlying PND, mediated by PUFAs.