Xenoestrogen
Xenoestrogens are clinically significant because they can mimic the effects of endogenous estrogen and thus have been implicated in precocious puberty and other disorders of the reproductive system.
Progestin
The androgenic activity of testosterone-derivative progestins and other progestins that have androgenic activity can be roughly ranked as follows:It should be noted however that the clinical androgenic and anabolic activity of the androgenic progestins listed above is still far lower than that of conventional androgens and anabolic steroids like testosterone and nandrolone esters. As such, they are only generally associated with such effects in women and often only at high dosages. In men, due to their concomitant progestogenic activity and by extension antigonadotropic effects, these progestins can have potent functional antiandrogenic effects via suppression of testosterone production and levels.
On the other hand, some progestins have antiandrogenic activity in addition to their progestogenic activity. These progestins, with varying degrees of potency as antiandrogens, include chlormadinone acetate, cyproterone acetate, dienogest, drospirenone, medrogestone, megestrol acetate, nomegestrol acetate, osaterone acetate (veterinary), and oxendolone. The relative antiandrogenic activity in animals of some of these progestins has been ranked as follows: cyproterone acetate (100%) > nomegestrol acetate (90%) > dienogest (30–40%) ≥ chlormadinone acetate (30%) = drospirenone (30%). Antiandrogenic activity in certain progestins may help to improve symptoms of acne, seborrhea, hirsutism, and other androgen-dependent conditions in women.