How are IgG and Fruchtbarkeit related?

The relationship between IgG and fertility is not clearly established in science. IgG antibodies are part of the adaptive immune system and play a role in immune defense. In the context of fertility, two aspects are mainly discussed: (1) Antisperm antibodies (ASA) of the IgG type can impair sperm motility or fertilization in both men and women – this is a recognized but rare mechanism of immunological infertility. (2) IgG-based food sensitivity tests (e.g., IgG4 against foods) are marketed by some companies to improve fertility, but robust clinical studies proving a causal link are lacking. Chronic inflammation from undetected food intolerances could theoretically affect fertility, but IgG tests are not validated for this purpose. The evidence level is therefore 'mixed' to 'unclear'. Anyone experiencing fertility issues should consult specialized physicians and not rely on DTC IgG tests.