Evidence check: Fertility Check | Fruchtbarkeits-Test in the context of blood sugar

The query combines a 'Fertility Check' with blood sugar – an area where the evidence needs careful differentiation. A direct DNA test for 'fertility' that includes blood sugar markers is not scientifically established. While it is known that insulin resistance and impaired glucose metabolism (e.g., in PCOS) can affect fertility, the genes mentioned in the context (SLCO1B1, CYP1A2, CYP2C9, CAT) have no proven direct impact on fertility. SLCO1B1 is involved in statin and bilirubin transport, CYP1A2 in caffeine metabolism, CYP2C9 in drug processing, and CAT in antioxidant capacity. None of these genes are associated with fertility parameters or blood sugar regulation in high-quality studies. Therefore, the evidence for such a test is 'unclear' or 'marketing'. A fertility check should rely on validated markers like AMH, FSH, or insulin resistance – not on single SNPs without reproductive relevance. Caution is advised against overblown claims: blood sugar is one factor, but not a sole predictor of fertility.