Semen quality in men with cancer: comparison with a healthy Swiss reference population.

Cancer and its treatment can reduce fertility in men of reproductive age and can affect the ability to have children. It is still unclear how much of this effect is caused by the disease itself and how much by the treatment. In this study, we compared semen quality in men with cancer before and after treatment with that of healthy Swiss men. We found that some patients, especially those with testicular cancer, already had lower semen quality before starting the treatment. After treatment, semen quality often further decreased and more men had no sperm in their ejaculate. This was particularly seen in patients who received treatments known to strongly affect fertility. These findings show that both cancer and cancer treatment can impair male fertility. This highlights the importance of early counselling and offering sperm freezing before treatment, as well as providing long-term reproductive follow-up after cancer care.