How are B12 and Fruchtbarkeit related?

The relationship between vitamin B12 and fertility is recognized in medical literature, but the evidence is primarily mechanistic and observational. B12 is crucial for DNA synthesis, cell division, and homocysteine metabolism. Elevated homocysteine—often due to B12 deficiency—has been associated with female infertility, recurrent pregnancy loss, and male subfertility (impaired sperm quality). However, isolating a direct causal role of B12 is difficult because deficiency often coexists with other nutritional and lifestyle factors. The provided context contains no specific studies on B12 and fertility; this answer relies on general medical knowledge. Genetic testing for B12-related variants (e.g., in MTHFR, FUT2) has limited predictive value—direct measurement of serum B12, holotranscobalamin, and homocysteine is far more informative. MyBody-X may include such SNPs, but effect sizes are small. Supplementation is beneficial when deficiency is confirmed, but unnecessary high doses do not enhance fertility. Conclusion: B12 is relevant but not a standalone solution; lab testing outperforms genetic screening for this question.