Evidence check: CYP2C19 in the context of Fruchtbarkeit

The evidence for CYP2C19 in fertility is weak. CYP2C19 is a drug-metabolizing enzyme, primarily relevant for medications like clomiphene and letrozole used in fertility treatments. Some studies suggest that genetic variants (*2, *3, *17) may modestly affect drug metabolism and treatment outcomes, but effect sizes are small, population-specific, and not clinically actionable. No major medical society recommends routine CYP2C19 testing for fertility. Direct-to-consumer tests often overstate the relevance. Evidence is 'mixed': mechanistic plausibility and a few association studies exist, but no RCTs demonstrate benefit. Dietary or supplement adjustments based on CYP2C19 are unsupported. Fertility management should rely on established clinical protocols.