The role of over-the-counter supplements for the treatment of male infertility--fact or fiction?

Many over-the-counter (OTC) vitamins and supplements have been used to improve male fertility. The purpose of this study is to review the effects of these OTC supplements on male fertility. A Pub Med and Medline review of the randomized controlled studies utilizing OTC vitamins and supplements readily available in the United States over the last 3 decades was performed. Many studies demonstrate the positive effects of OTC supplementation on semen parameters and pregnancy outcomes. Conversely, many studies also demonstrate a lack of improvement and potential complications with supplementation. Confounding factors include lack of standard dosing regimens, duration of treatment, and control for dietary intake. No standard exists for which OTC supplement and vitamin studies have been conducted or the medications dosed. Definitive conclusions as to their true effects on male subfertility and dosing regimen could not be identified.