Antioxidants may reduce infertility

Antioxidant supplements may improve sperm quality and pregnancy rates, according to a new UK review.

In the systematic review, 17 randomized controlled clinical trials and data from 1,665 men were analyzed to investigate a potential relationship between the intake of supplements containing vitamin C, vitamin E, vitamin B9 (folate), carotenoids, zinc and/or selenium and sperm quality (1). The results showed that in 75 percent of the trials antioxidant supplementation was associated with an improvement in at least one sperm parameter compared with placebo or no treatment. Sixty-three percent of the studies showed significant improvements in sperm motility compared with placebo, while 33 percent of trials showed an improvement in sperm concentration. Regarding pregnancy rates, the review reports that antioxidant supplementation was associated with a higher pregnancy rate of 19 percent, compared with only 3 percent in placebo/control groups.

The researchers commented that the increased pregnancy rates could possibly be explained by the antioxidant-related improvement in either sperm motility or total motile sperm count, both of which have been reported to predict male fertility or sperm DNA integrity. However, the evidence is not consistent and more studies are therefore required before antioxidant supplements can be recommended to infertile men, they added.

The link between antioxidants and fertility measures is not new: oxidative stress has been reported to reduce the quality of sperm. About 15 percent of couples of reproductive age are affected by infertility issues, with 50 percent of these cases related to impaired semen.

1. Ross C. et al. A systematic review of the effect of oral antioxidants on male infertility. Reproductive BioMedicine Online. 2010; 20:711–723.