Concerns regarding the association of occupational testicular radiation exposure with offspring sex ratio.

We read with great interest the recent article by Hijikata et al. examining the association between occupational testicular radiation exposure in spine surgeons and the sex ratio of their offspring. This paper addresses a rumor circulating among healthcare workers, aiming to enhance radiation protection for them (Hijikata et al. 2025). We would like to express our respect for the authors' ambitious efforts. However, we have concerns regarding the study's methodology and interpretation of the results, which may lead to misleading conclusions. While the sex ratio in the high-exposure group was slightly lower at 88.9 (P = 0.069; Hijikata et al. 2025), the contrast between groups (the risk ratio of 1.35) appears to be driven largely by the unusually high sex ratio of 156 in the control group, rather than by radiation reducing male offspring in the exposed group. Given the small sample size of the control group (Suzuki et al. 2016), this deviation may reflect systematic or selection bias. Several candidates merit consideration: