Balercia G et al. (2008) Coenzyme Q10 treatment in infertile men with idiopathic asthenozoospermia: a placebo-controlled, double-blind randomized trial. Fertil Steril [doi:10.1016/j.fertnstert.2008.02.119]

Evidence suggests that oxidative stress has detrimental effects on male fertility, and deficiency of coenzyme Q10, which is both an antioxidant and an important component of the energy-generating electron-transport chain, has been associated with infertility. An Italian randomized controlled trial has found that coenzyme Q10 treatment improves sperm motility in men with idiopathic asthenozoospermia.

Balercia et al. randomly allocated 60 men (mean age 32 years) to receive daily coenzyme Q10 or placebo for 6 months. Semen samples were taken for analysis 1 month before the start of treatment, at treatment initiation, and at 3, 6 and 9 months after treatment commenced. Whereas placebo had no effect on semen characteristics, levels of coenzyme Q10 and of reduced coenzyme Q10 increased in both sperm cells and seminal plasma after 6 months of active treatment, and sperm cell total mobility and forward mobility increased in the coenzyme Q10 group. After a 3-month washout period, however, sperm characteristics returned to baseline levels. Nine spontaneous pregnancies occurred during the study: six in partners of treatment-group participants, and three in partners of placebo-group participants.

The authors conclude that coenzyme Q10 administration has a beneficial effect on sperm motility, possibly because of its antioxidant qualities and/or effects on energy metabolism, and is a potential treatment for idiopathic asthenozoospermia.