热暴露与男性生育力存在明确关联。一项2024年中国研究追踪了超过15,000名男性，分析了28,000多份精液样本，发现极端温度暴露与精子质量下降相关，具体表现为精子浓度、总数和活动能力的降低[1]。意大利纵向研究进一步证实了这一点：10名健康男性每周进行两次15分钟、80-90°C的芬兰桑拿浴，坚持3个月后，其精子数量和活动能力出现下降[1]。然而这些变化具有可逆性，停止使用桑拿后6个月内可恢复[1]。
美国研究显示，热水浴和热水浴缸单独对妊娠率的影响甚微，但对多个热源累积暴露较多的男性，受孕机会会中等程度降低[1]。与此相比，冷水浸泡虽然可能减少肌肉酸痛并促进运动后短期恢复，但澳大利亚系统评价研究未发现证据表明其能改善睾酮、精子质量或妊娠率[1]。值得注意的是，睾酮和生育力并非同一概念，提高血睾酮水平不会自动提高精子质量或改善受孕可能性[1]。
Recent research examining the effects of extreme temperatures on male reproductive health reveals that heat poses measurable risks to sperm quality, while evidence for cold water immersion remains inconclusive. A 2024 Chinese study tracking over 15,000 men and analyzing more than 28,000 semen samples found that exposure to extreme temperatures correlates with declines in sperm concentration, total count, and motility [1]. An Italian longitudinal study demonstrated that ten healthy men who underwent Finnish sauna sessions twice weekly for 15 minutes at 80-90°C over three months experienced reduced sperm count and activity, though these changes reversed within six months of ceasing sauna use [1].
The fertility impact of heat exposure appears dose-dependent. American research indicated that hot baths and hot tubs alone have minimal effect on pregnancy rates, but men with cumulative exposure to multiple heat sources experienced moderate reductions in conception likelihood [1]. In contrast, cold water immersion, while potentially beneficial for reducing muscle soreness and promoting short-term post-exercise recovery, lacks evidence supporting improvements in testosterone levels, sperm quality, or pregnancy rates [1]. Importantly, researchers note that elevated blood testosterone does not automatically translate to improved sperm quality or increased chances of conception [1].
