Purpose: Testicular germ cell tumors (TGCT) are the most common solid organ malignancy in young men. It is a largely curable disease, so the extent to which it affects quality of life-including male fertility-is important. Abnormal semen analysis is highly predictive of male infertility. We conducted a systematic review of published studies that reported pre-orchiectomy semen parameters (as a surrogate for fertility) in TGCT patients to evaluate the association between TGCT and semen abnormalities before orchiectomy. Methods: We conducted a systematic review of peer-reviewed publications reporting semen parameters before orchiectomy in adult patients diagnosed with TGCT. Further, we assessed the association between TGCT and semen abnormalities that may lead to infertility. Results: We applied MeSH search terms to four online databases (PubMed, Cochrane Reviews, Web of Science, and Ovid), resulting in 701 potentially relevant citations. After conducting a three-stage screening process, six articles were included in the systematic review. For each study, the participants' data and the study's quality and risk of bias were assessed and described. All studies showed semen abnormalitiesincluding count, motility, and morphology-in men with TGCT prior to orchiectomy. Conclusions: TGCT is associated with semen abnormalities before orchiectomy. This review shows an increase in abnormal semen parameters among men with TGCT even outside the treatment effects of orchiectomy, radiation, or chemotherapy. To improve long-term quality of life, these findings should be considered when counseling patients on future fertility and sperm banking during discussions about treatment and prognosis for TGCT.Keywords: germ cell tumor, semen analysis, orchiectomy, fertility, testicular cancer T esticular germ cell tumors (TGCT) are the most common solid organ malignancy in young men (ages 15-34), with overall 5-year survival over 95%.1 It is a highly curable disease, with fertility morbidity either directly from the cancer or from its treatments. As TGCT typically occurs at a young age-and often prior to paternity-patients should be counseled about the extent to which it affects male fertility, as it can contribute to a patient's quality of life. Currently, there are an estimated 1.5 million infertile couples in the United States; male infertility is involved in approximately 47% of these couples and approximately half of the infertile males have abnormal semen parameters. While many factors affect fertility, malignancy is clearly a culprit.3 As TGCT arise from germ cells, it has been hypothesized that testicular cancer might cause semen abnormalities that can lead to male infertility. 3 Treatment of TGCT in the forms of orchiectomy, chemotherapy, retroperitoneal lymph node dissection, and radiation can also lead to semen abnormality. 4,5 There are few studies that have examined the association between TGCT and semen abnormalities. Among those, most examined this association after orchiectomy or other TGCT treatment modalities. Subsequentl...