Levels of n-3 and n-6 fatty acids in maternal erythrocytes during pregnancy and in human milk and its association with perinatal mental health

Omega-3 long-chain polyunsaturated fatty acid (n-3 FA) status may be associated with mood disorders. Here, we evaluated the potential association between antenatal depression/anxiety and n-3/n-6 FA in (a) maternal erythrocytes and (b) human milk. In addition, we explored associations between n-3/n-6 FA in erythrocytes and in human milk and postpartum depression, while controlling for antenatal depression. Twenty-seven pregnant women diagnosed with a current major depressive disorder (MDD; n = 9), anxiety disorder (AD; n = 10) or a mixed anxiety-depression disorder (MADD; n = 8), and 40 healthy controls were included. n-3/n-6 FA were determined in maternal erythrocytes in gestational week 32 and in human milk in postpartum week 1. In the first week postpartum, the Edinburgh-Postnatal-Depression-Questionnaire was used to assess postpartum depression. Results show that women with M(A)DD had significantly lower erythrocyte levels of total n-3 FA, EPA, DHA and DGLA, and significantly higher n-6 DPA, and n-6:n-3, AA:EPA and n-6 DPA:DHA ratios compared to healthy controls. No significant associations between antenatal depression or anxiety and n-3/n-6 FA in human milk were found. After controlling for antenatal mental health, n-3/n-6 FA in maternal erythrocytes or in human milk were not significantly associated with postpartum depression. In conclusion, antenatal depression, alone or with an anxiety disorder, was associated with lower n-3 FA levels and higher n-6:n-3 FA ratios in maternal erythrocytes during gestation. This study provides some insights into the associations between n-3/n-6 FA levels during pregnancy and lactation and perinatal mental health.