Is VKORC1 useful for fertility?

There is no scientific evidence that VKORC1 is useful for assessing or improving fertility. VKORC1 encodes vitamin K epoxide reductase, an enzyme critical for vitamin K recycling and blood coagulation. Its well-known variants affect warfarin sensitivity, but no robust studies link VKORC1 polymorphisms to fertility outcomes such as ovulation, sperm quality, implantation, or live birth rates. Claims by some direct-to-consumer genetic tests that VKORC1 influences fertility are speculative and lack clinical validation. The evidence level is 'unclear' at best, and such tests are primarily marketing. For fertility concerns, proven biomarkers (e.g., AMH, FSH, semen analysis) and clinical evaluation remain the standard. Relying on VKORC1 genotyping for fertility decisions is not supported by current science and may lead to false expectations or unnecessary costs.