Evidence check: Fertility Check in the context of Langlebigkeit

A fertility check based on DNA markers has very limited value in the context of longevity. Most such tests analyze single genetic variants related to hormone metabolism or oxidative stress, but their effect sizes are small and they do not predict lifespan. Longevity is primarily determined by lifestyle factors (diet, exercise, sleep, stress management) rather than individual genes. Even polygenic risk scores for life expectancy explain less than 4% of variance. Therefore, a fertility check cannot be recommended as a tool for optimizing longevity. The evidence is largely marketing-driven. For improving fertility and long-term health, validated biomarkers (e.g., AMH, vitamin D status) and medical advice are more appropriate.