The cornerstone of the male fertility evaluation has traditionally been the conventional semen analysis. This assesses quantitative measures but does not offer a qualitative assessment of sperm. The sperm DNA fragmentation (SDF) test is the first functional sperm test that has enough research to support its use clinically. Although the indications for SDF testing will likely expand overtime, the current indications include men with varicoceles (dilated veins around the testicles), in couples with recurrent miscarriages, and in couples who failed IVF with “healthy” eggs. At the Westlake IVF andrology laboratories SDF testing is routinely performed. Dr. Parviz Kavoussi co-authored a recent study on the technical aspects of SDF testing.