In many contexts, the two main classes of<unk> s are androgens and estrogens, of which the most important human derivatives are testosterone and estradiol, respectively. Other contexts will include progestogens as a third class of<unk>  steroids, distinct from androgens and estrogens. Progesterone is the most important and only naturally occurring human progestogen. In general, androgens are considered "male<unk> s", since they have masculinizing effects, while estrogens and progestogens are considered "female<unk> s" although all types are present in each<unk>  at different levels.<unk> s include: * Progestogens * Pregnenolone → Progesterone → Allopregnanedione → Allopregnanolone * 17α-Hydroxypregnenolone → 17α-Hydroxyprogesterone * Androgens * Dehydroepiandrosterone → Androstenedione → Androstanedione → Androsterone * Androstenediol → Testosterone → Dihydrotestosterone → Androstanediol * Estrogens * 2-Hydroxyestrone ← Estrone → 16α-Hydroxyestrone * 2-Hydroxyestradiol ← Estradiol → Estriol → Estetrol
Sex hormone
Hormone
Local hormone
Gastrointestinal hormone
Xenohormone
Estrogen 
Estrogen
Androgen