LAUSR

© P .K H A M G U LA /S H U TT ER ST O C K reproductive techniques and the fathers of those conceived naturally. The fathers were grouped according to fertility status by mode of conception, which included in vitro fertilization (IVF; 20,618 [1.7%]), intracytoplasmic sperm injection (ICSI; 14,882 [1.3%]), and natural conception (1,145,990 [97%]). Cancer registries were used to identify new cases of prostate cancer up to 20 years after childbirth. Investigators adjusted for factors such as age and education level. The average age at childbirth for men who were treated with either IVF or ICSI was 37 years, whereas the average age for fathers who conceived naturally was 32 years. The findings showed the following: • Among men who achieved fatherhood naturally, 3244 (0.28%) were diagnosed with prostate cancer, whereas 77 of the men in the IVF group (0.37%) and 63 in the ICSI group (0.42%) were. • Among men who fathered children through ICSI, the risk of early-onset prostate cancer was particularly high, even after the exclusion of men who had had a previous cancer diagnosis or had received testosterone replacement therapy. ICSI is used by men with the most severe infertility. The study is observational and thus cannot point to causes for the increased risk. In addition, the authors point to several limitations. First, they did not include men who were unable to father children and who may have had a higher risk of prostate cancer than those who did conceive children. Moreover, the average age at the end of the follow-up in the study was 45 years, and this limited the ability to quantify prostate cancer risk over a lifetime. Nevertheless, according to the researchers, the findings indicate that the ICSI-assisted group, in particular, may benefit from testing and long-term follow-up, and they add that a possible link between infertility and prostate cancer risk might be related to abnormalities on the Y chromosome in both conditions. However, they caution that screening all infertile men for prostate cancer carries the potential for overdiagnosis and overtreatment. For those reasons, they recommend additional research in this area.