MAASTRICHT, THE NETHERLANDS. About 20% of Dutch women develop post-partum depression shortly after giving birth with the peak incidence reached about 32 weeks post-partum. There is growing evidence of an association between low blood levels of docosahexaenoic acid (DHA), a major component of fish oil, and post-partum depression (PPD). Dutch researchers report that it may not be DHA level per se that is the important factor, but rather the increase in DHA availability, or DHA functional status following birth. Availability is expressed as the ratio of DHA to DPA (docosapentaenoic acid). DPA is the intermediary step in the conversion of EPA (eicosapentaenoic acid) to DHA. DHA availability is reduced during pregnancy and normalizes following delivery; however, it this normalization is slow depression may result.
The Dutch study involved 112 pregnant women who had blood samples collected at week 36 of pregnancy, immediately following delivery, and 32 weeks post-partum. At week 32 post-delivery the women were assessed for the presence of PPD using the Edinburgh Postnatal Depression Scale (EPDS) questionnaire. Twenty-four of the women (21%) were found to suffer from depression (EPDS score equal to or greater than 10). Seventy-five percent of the depressed women rated themselves as “not healthy” in the months following delivery as compared to only 6% in the non-depressed group (EPDS score less than 10).
The researchers did not observe any statistically significant relationship between post-partum depression and DHA level as such; however, they did find a significant correlation between PPD and the increase in DHA:DPA ratio between delivery and 32 weeks post-partum. Women with a slower increase in this ratio had a 10% higher risk of PPD. There was no indication that breast-feeding increased the risk of PPD. The researchers recommend further studies, but suggest that women who have recently given birth increase their intake of DHA.
Otto, SJ, et al. Increased risk of postpartum depressive symptoms is associated with slower normalization after pregnancy of the functional docosahexaenoic acid status. Prostaglandins, Leukotrienes and Essential Fatty Acids, Vol. 69, 2003, pp. 237-43