The burden of fatherhood
The results of a study conducted by Swedish scientists indicate that men who have conceived a child using artificial insemination methods may benefit from early screening and long-term monitoring of prostate cancer.
Prostate cancer and infertility in the West affect about 10% and 8% of men, respectively. Since prostate cancer and many forms of infertility are associated with male sex hormones, they could also be related to each other. This possible correlation has already been investigated before, but the studies had certain drawbacks that prevented scientists from making any accurate conclusions.
This time, scientists decided to compare the risk and severity of prostate cancer between men who used assisted reproduction methods and those who conceived a child naturally.
Scientists compared data on the birth of more than a million children in Sweden during 1994-2014, with the same number of fathers.
Men were grouped according to fertility status by method of conception: 20,618 (1.7%) by in vitro fertilization (IVF), 14,882 (1.3%) by sperm injection (ICSI) and 1,145,990 (97%) naturally.
The average age of men who used IVF and ICSI methods was 37 years; those who conceived a child on their own – 32 years. Cancer registries were used to identify new cases of prostate cancer up to 20 years after childbirth.
After adjusting for factors that could affect the results (age and level of education), the researchers found that men who became fathers as a result of IVF and ICSI had a significantly higher risk of developing prostate cancer.
Prostate cancer was diagnosed in 3244 men (0.28%) who conceived a child naturally, compared with 77 (0.37%) in the IVF group and 63 (0.42%) in the ICSI group.
Risk of early prostate cancer (diagnosed before age 55) It was also particularly high for men who used ICSI, a technology used for men with the most severe forms of infertility.
The increased risks persisted even after the exclusion of men with previously diagnosed oncological diseases or who received hormone replacement therapy with testosterone. However, early screening of men at risk does not have much benefit for survival and often leads to overdiagnosis and overtreatment, which rarely have a positive effect on the patient's health.
Unfortunately, this observational study does not establish the cause, and the authors point out some limitations. For example, they did not include infertile men who were unable to become fathers and could have a higher risk of developing prostate cancer than those who used the services of assisted reproduction clinics.
Moreover, with an average age of 45 years at the end of the follow-up period, these results cannot quantify the risk of developing prostate cancer during life.
How male infertility can be biologically linked to the risk of prostate cancer is still unclear, but scientists suggest abnormalities in the Y chromosome.
Article by Al-Jebari et al. Risk of prostate cancer for men fathering through assisted reproduction: nationwide population based register study published in the journal The BMJ.
Elena Panasyuk, portal "Eternal youth" http://vechnayamolodost.ru according to Eurekalert: Fathering children by assisted reproduction linked to increased risk of prostate cancer.