Transgender hormone therapy (male-to-female) medical professional. Inducers of CYP3A4 and other cytochrome P450 enzymes can reduce the effects of MTF HRT. A variety of different sex-hormonal medications are used in feminizing hormone therapy for transgender women. These include estrogens to induce feminization and suppress testosterone levels; antiandrogens such as androgen receptor antagonists, antigonadotropins, GnRH modulators, and 5α-reductase inhibitors to further oppose the effects of androgens like testosterone; and progestogens for various possible though uncertain benefits. Estrogens are the major sex hormones in women, and are responsible for the development and maintenance of feminine secondary sexual characteristics, such as breasts, wide hips, and a feminine
Transgender hormone therapy (male-to-female) voice deepens in pitch and becomes more resonant. These changes are permanent and are not affected by HRT. Voice therapy and/or surgery may be used instead to achieve a more female-sounding voice. Facial hair develops during puberty and is only slightly affected by HRT. It may, however, be eliminated nearly permanently with laser hair removal, or permanently with electrolysis. The psychological effects of feminizing hormone therapy are harder to define than physical changes. Because hormone therapy is usually the first physical step taken to transition, the act of beginning it has a significant psychological effect, which is difficult to distinguish