What do studies say about Haarausfall Frauen?

The provided context does not contain specific studies on female hair loss. In general medical knowledge, female hair loss (alopecia) is multifactorial: androgenetic alopecia (genetic, hormonal), telogen effluvium (stress, diet), deficiencies (iron, zinc, vitamin D), or autoimmune conditions. Studies show involvement of androgen receptors and 5α-reductase, but evidence for direct genetic testing (e.g., FTO) for hair loss is weak. Consumer DNA tests often lack clinical utility. Persistent hair loss warrants medical evaluation (dermatologist, endocrinology). Since the context lacks direct studies, the evidence level is marked as 'unclear'.