Evidence check: FUT2 in the context of Fruchtbarkeit

The FUT2 gene encodes a fucosyltransferase that determines secretor status—whether ABO blood group antigens are secreted into bodily fluids. Some studies have explored links between FUT2 variants and fertility outcomes, such as recurrent miscarriage or susceptibility to reproductive tract infections. However, the evidence is weak: most findings come from small candidate-gene studies without robust replication in large cohorts. No clinically actionable effect has been established, and FUT2 testing is not part of standard fertility workup. Direct-to-consumer DNA tests that include FUT2 often overstate its relevance. Established factors like age, hormone levels, lifestyle, and organic causes are far more important. The evidence for FUT2 in fertility is therefore best rated as unclear.