Evidence check: BDNF in the context of Fruchtbarkeit

BDNF (Brain-Derived Neurotrophic Factor) is increasingly studied in the context of fertility, particularly regarding oocyte maturation, sperm quality, and embryo implantation. Evidence comes mainly from animal models and small human studies suggesting that low BDNF levels may be associated with reduced fertility. However, the data are not yet robust enough to recommend BDNF as a clinical biomarker or therapeutic target for fertility. Most consumer tests measuring BDNF lack validated reference ranges for reproductive health. Additionally, BDNF is strongly influenced by lifestyle factors (exercise, stress, diet), making interpretation difficult. There is no strong evidence that altering BDNF levels directly improves fertility outcomes. Therefore, the evidence grade is 'human-moderate' with the caveat that BDNF alone should not guide fertility decisions. Safety note: Do not supplement BDNF without medical supervision due to its role in neural plasticity and potential off-target effects.