Hormone replacement therapy (male-to-female)

Hormone replacement therapy (HRT) for transgender and transsexual people changes the balance of sex hormones in their bodies. Some intersex people also receive HRT, either starting in childhood to confirm the sex to which they were assigned, or later, if this assignment has proven to be incorrect.

Its purpose is to cause the development of the secondary sex characteristics of the desired sex. It cannot undo many of the changes produced by the first natural occurring puberty, which may necessitate surgery and/or epilation (see below).

The ICD-10 criteria for Transsexualism include the individual having a transsexual identity of over 2 years, a strong and persistent desire to live as a member of the opposite sex, usually accompanied by the desire to make their body as congruent as possible with the preferred sex through surgery and hormone treatments. These individuals cannot be diagnosed with Transsexualism if it is believed to be a result of another mental disorder, or a genetic, intersex or chromosomal abnormality.

The ICD-10 criteria for Gender identity disorder of childhood in males include the individual being pre-pubescent and having intense and persistent distress about being a boy. The distress must be present for at least six months. The child must either:

1. Have a preoccupation with stereotypic female activities, as shown by crossdressing, simulating female attire, or an intense desire to join in the games and pastimes of girls, rejecting male games and pastimes.
2. Have persistent denial relating to their male anatomy. This can be shown through believing they will grow up to be a woman, that their penis or testes is disgusting or will disappear, or that it would be better not to have a penis.

The DSM-IV-R criteria for Gender Identity Disorder includes four main criteria. The DSM-IV-R also requests that the individual's sexuality is noted.

Strong and persistent cross-gender identity.

In children this may be demonstrated by them meeting four or more of the following criteria:

1. An insistence that one is or desires to be the other sex.
2. Boys must display a preference crossdressing or simulating female attire, and girls must persistently wear only stereotypical male clothing.
3. Persistent fantasies of being the other sex, or strong and persistent preference for cross-sex roles in make-believe play.
4. Intense desire to participate in stereotypical games of the other sex.
5. Strong preference for playmates of the other sex.

Persistent discomfort with their sex or a sense of inappropriateness in the gender role of that sex.

In boys this may manifest as an assertion that their penis or testes are disgusting or will disappear, or asserting that it is better not to have a penis.

In adults and adolescents this manifests as a preoccupation with removing primary or secondary sex characteristics, such as a demand for surgery or hormone replacement therapy.

The disturbance must not be concurrent with a physical intersex condition.

The disturbance causes clinically significant distress or impairment in social, occupations or important areas of functioning.

The DSM-V moves from Gender Identity Disorder to Gender Dysphoria to avoid the implication that gender nonconformity is in itself a mental disorder, but a similar entry remains in the DSM-V so that individuals may still seek treatment. The DSM-V, unlike the DSM-IV and ICD-10, separates Gender Dysphoria from sexual paraphilias, and diagnoses on the basis of a strong desire that one has feelings and convictions typical of the other sex, or that one strongly desires to be treated as the other sex or be rid of one's sex characteristics.

The readability of patients to transition is also relevant to undertake hormone replacement therapy, which includes the patient's likelihood to take hormones in a responsible manner, have made progress in mastering other identified problems that leads to improving or continuing stable mental health, and have had further consolidation of gender identity during psychotherapy or Real Life Experience of their desired gender role.^[3]

Some organizations still require a period of time living as the desired gender role, based on standards such as the Standards of Care for the Health of Transsexual, Transgender, and Gender Nonconforming People (WPATH). This period is sometimes called the Real Life Experience (RLE). Endocrine Society in 2009 specified that individuals should either have a documented 3 months Real Life Experience or a period of psychotherapy of length specified by the mental health provider, usually a minimum of 3 months.

Some people, especially individuals from the transgender community, say that RLE is psychologically harmful and is a form of "gatekeeping" — effectively barring people from transitioning for as long as possible, if not permanently.

Some individuals choose to self-administer their medication ("do-it-yourself"), often because available doctors have too little experience in this matter, or no doctor is available in the first place. Sometimes, trans persons choose to self-administer because their doctor will not prescribe hormones without a letter from the patient's therapist stating that the patient meets the diagnostic criteria for GID and is making an informed decision to transition. Many therapists require at least three months of continuous psychotherapy and/or a real life test in order to write such a letter as is suggested in the HBIGDA Standards of Care. In these circumstances, the individual may self-administer until they can get these authorizations, feeling that they shouldn't have to wait for a medical professional to be convinced of their situation. In addition, as many individuals must pay for evaluation and care out-of-pocket, expense can also be prohibitive to pursuing such therapy.

However, self-administration of certain hormones (namely ethinyl estradiol) and anti-androgens (namely cyproterone acetate, flutamide, and nilutamide) is potentially dangerous and can cause an elevation in liver enzymes.