Is B12 useful for Fruchtbarkeit?

Vitamin B12 is relevant for fertility because it plays a key role in DNA synthesis, cell division, and homocysteine metabolism. Elevated homocysteine levels are linked to infertility, miscarriage, and poor egg/sperm quality. Some studies suggest B12 supplementation may improve fertility outcomes, especially in individuals with a confirmed deficiency or high homocysteine. However, the evidence is moderate: no large randomized controlled trials show a clear benefit for the general population. In men, B12 may improve sperm parameters, but data are limited. A blood test for B12 and homocysteine is recommended before supplementing. Typical doses (2.4 µg/day) are safe, but high doses without deficiency are not proven to help. Caveat: B12 is not a standalone fertility solution; overall health, diet, and other factors matter more.