Effect of dietary supplementation with a highly pure and concentrated docosahexaenoic acid (DHA) supplement on human sperm function.

The aim of this study was to evaluate the possible beneficial effects of diet supplementation with a highly concentrated and purified docosahexaenoic acid (DHA) formula on human sperm function. We performed a prospective, randomized, double blind, placebo-controlled intervention study. One-hundred eighty human semen samples from sixty infertile patients recruited in a private assisted reproduction center were included. All samples were examined according to World Health Organization guidelines. We analyzed macroscopic and microscopic sperm parameters, oxidative stress, apoptosis, lipid peroxidation, mitochondrial membrane potential and DNA fragmentation before and after supplementation with different DHA daily doses (0.5, 1 and 2 g) or placebo for 1 and 3 months. No differences were found in traditional sperm parameters except for progressive sperm motility, with a significant increase after DHA ingestion after the first month with 1 or 2 g doses and after 3 months with 0.5 g of DHA. This effect was more evident in asthenozoospermic patients. No differences were found in any molecular semen parameter except oxidative stress, in which a slight benefit was observed after DHA treatment. In conclusion, this study support previous indications that highlight the importance of DHA supplementation as a means of improving sperm quality in asthenozoospermic men.