Supplements and semen quality
Some drugs and nutritional supplements can improve semen quality but there is little evidence that it leads to improved pregnancy rates, according to a paper published in European Urology (doi.org/10.1016/j.eururo.2018.12.022).
A large analysis of 61 published studies found that pentoxyfylline, coenzyme Q10, L-carnitine, follicle-stimulating hormone, tamoxifen, and kallikrein all improved semen parameters. Other drugs and supplements were found to improve semen quality, but the individual studies had methodological flaws.
There is very limited evidence that empiric therapy leads to better live birth rates, spontaneous pregnancy, or pregnancy following assisted-reproductive techniques.
According to the authors, empiric use of medical and nutritional supplements to improve semen quality and thus pregnancy rates in couples with idiopathic infertility has reached global proportions. However, as this study shows, the evidence base for their use in this setting is controversial.