How are STI Test and Fruchtbarkeit related?

The provided knowledge contexts do not contain any information linking STI tests and fertility. Medically, STIs (e.g., chlamydia, gonorrhea) can impair fertility if untreated, but the given context covers DNA tests, microbiome, hormones, and sports – not STI diagnostics or fertility. Without relevant sources, no evidence-based relationship can be established. A proper answer would require specific studies or guidelines on STI screening and fertility outcomes.