Effect of DHA supplementation on DHA status and sperm motility in asthenozoospermic males

The effects of supplementation with docosahexaenoic acid (DHA) on DHA level s in serum, seminal plasma, and sperm of asthenozoospermic men as well as o n sperm motility were examined in a randomized, double-blind, placebo-contr olled manner. Asthenozoospermic men (n = 28; less than or equal to 50% moti lity) were supplemented with 0, 400, or 800 mg DHA/d for 3 mon. Sperm motil ity and the fatty acid composition of serum, seminal plasma, and sperm phos pholipid were determined before and after supplementation. In serum, DHA su pplementation resulted in decreases in 22:4n-6 (-30% in the 800-mg DHA grou p only) and total n-6 (-6 and -12% in the 400- and 800-mg DHA groups, respe ctively) fatty acids. Increases were noted in DHA (71 and 131% in the 400- and 800-mg DHA groups, respectively), total n-3 fatty acids (42 and 67% in the 400- and 800-mg DHA groups, respectively), and the n-3/n-6 ratio (50 an d 93% in the 400- and 800-mg DHA groups, respectively). In seminal plasma, DHA supplementation resulted in a decrease in 22:4n-6 (-31% in the 800-mg D HA group only) and an increase in the ratio of n-3 to n-6 (35 and 33% in th e 400- and 800-mg DHA groups, respectively). There were insignificant incre ases in DHA and total n-3 fatty acids. In sperm, decreases were noted in 22 :4n-6 (-37 and -31% in the 400- and 800-mg DHA groups, respectively). There were no other changes. There was no effect of DHA supplementation on sperm motility. The results show that dietary DHA supplementation results in inc reased serum-and possibly seminal plasma-phospholipid DHA levels, without a ffecting the incorporation of DHA into the spermatozoa phospholipid in asth enozoospermic men. This inability of DHA to be incorporated into sperm phos pholipid is most likely responsible for the observed lack of effect of DHA supplementation on sperm motility.