Conclusion
This large registry-based study has suggested that infertile men may be at increased risk of high-grade prostate cancer. There are a number of points to note:
This study relied on data recorded as part of routine practice. Some data may have been misrecorded, and some information may be missing. For example, men who moved out of California and were diagnosed with cancer would not have been identified. This may affect the reliability of the results.
As the authors themselves note, some other studies have found no link between fertility and risk of prostate cancer. This may be because these studies relied on lack of offspring to indicate infertility, and all men without children are not necessarily infertile.
As with all observational studies, it is possible that other fa…