A study published in the August 2012 issue of the Journal of Urology reports that ubiquinol, the reduced form of the antioxidant coenzyme Q-10, could be useful in treating male infertility  

Infertility affects about one in six couples. The male partner is the cause in approximately 40 percent of cases, according to the National Institutes of Health. 

A total of 228 infertile men were enrolled in this new study. All of them had oligoasthenozoospermia—a condition in which they didn’t make enough sperm and their sperm also didn’t swim hard enough to reach the egg—in at least two semen samples obtained one month apart prior to starting treatment.  

Randomly divided into two groups, 114 men took 200 mg of ubiquinol supplements each day for six months while the other 114 men took a placebo. All of the men’s semen was analyzed at the start of the study, every month during the study and for three months afterward.

Researchers found that sperm counts in the men who took ubiquinol increased steadily during treatment, but there were no improvements in the men who received the placebo

In the ubiquinol group, after two months, sperm concentration increased 15 percent. After four months it was up 44 percent, and after 6 months the increase was 82 percent. Sperm motility, a measure of swimming prowess, increased 18 percent after three months, 27 percent after five months and 32 percent after six months. Morphology, or the shape of the sperm, also improved steadily during the course of treatment. Notably, once the men stopped taking ubiquinol, these improvements gradually faded away. 

While this study did not measure the bottom line—whether the partners of these men became pregnant while they were using ubiquinol—it certainly suggests that taking the supplement can  be useful. Because sperm improvements were steady but slow, the study results also suggest that infertile men need to be patient when taking ubiquinol. These men stopped the treatment after six months, just at the point that their sperm were looking healthy.