When is MTHFR Frauen actually useful?

The question of when MTHFR testing is useful for women requires a nuanced, evidence-based answer. The common variants (C677T, A1298C) are highly prevalent (30–50% of Europeans carry at least one) and have modest effects on folate metabolism. Clinically, testing may be considered in women with recurrent pregnancy loss, a history of neural tube defects, or elevated homocysteine levels. However, major guidelines (e.g., ACOG, DGGG) do not recommend routine MTHFR screening. Evidence for benefits in general fertility, thrombosis, or depression is weak or conflicting. Direct-to-consumer tests often overstate the impact, leading to unnecessary supplementation with methylfolate instead of standard folic acid. In practice, measuring blood homocysteine and folate is more actionable than genetic testing alone. Therefore, MTHFR testing is only useful in specific clinical scenarios, not as a general wellness tool.