Myths vs facts: MC4R and Fruchtbarkeit

Myths vs. Facts: MC4R and Fertility **Myth:** A variant in the MC4R gene directly causes infertility. **Fact:** MC4R is a key regulator of appetite and energy balance. Certain variants (e.g., rs17782313) are associated with obesity. Obesity can impair fertility through hormonal imbalances, insulin resistance, or ovarian dysfunction. However, a direct, obesity-independent effect of MC4R on reproduction is not well-established. Evidence comes from association studies and animal models, not from human randomized trials. **Bottom line:** Direct-to-consumer MC4R tests do not predict your fertility. For fertility concerns, clinical evaluation (hormone panel, semen analysis, genetic counseling if indicated) and lifestyle factors (diet, weight) are essential. A single gene test is not diagnostic.