A follow-up study for estimating the effectiveness of a cross-gender hormone substitution therapy on transsexual patients

© Archives of Sexual Behavior : 10/1998

Authors – Schlatterer, Kathrin; Yassouridis, Alexander; Werder, Klaus von; Poland, Dorette; Kemper, Johannes; Stalla, Gunter K.

Introduction

Gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
dysphoric disorders have been known from antiquity onward across national and cultural boundaries. They have been described in classic literature from Heroditus to Shakespeare (Pauly, 1965; Green, 1966). Historically, no difference was made between transsexualism• This term is used to describe a person who has “transitioned”, or is in the process of “transitioning”, or intends to transition from male to female or female to male. For a transsexual person, the process of “transitioning”, may involve a variety of treatments including: hormone therapy, surgery and hair removal. People who have transitioned do not necessarily identify as trans any longer; they may identify as simply a man or a woman. Some transsexual people may not transition due to family or other social constraints.
• When people complete their transition, they may no longer regard themselves as part of the trans umbrella. They might consider having been transsexual to just be an aspect of their medical history which has now been resolved and so is no longer an issue in their life. In such cases, they simply describe themselves as men or as women and it is most disrespectful to insist on calling them trans, transgender or transsexual against their wishes.
and transvestism due to the lack of technical opportunities for sexual conversion like hormone application and sex reassignment surgerySee gender-affirming surgery.. Beside the extreme solution of castration, clothing and cosmetics were the only tools available for both groups of individuals. A hormonal sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. change became feasible after the discovery of the sex hormonesHormones, such as oestrogen and testosterone, affecting sexual and reproductive development or function. early in the 20th century, and their successful synthesis and commercial manufacture in the 1930s. During the last decades in Western Europe and the United States multistep concepts for the treatment of transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients, in which cross-gender hormone application plays the central role, have been developed and continuously improved. Our strategy for cross-gender hormone treatment was refined during the follow-up of 129 transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients treated in our neuroendocrinological outpatient clinic over the last 5 years (Schlatterer et al., 1996). Of those patients, 88 have been included in the present study. Treatment concepts, psychosocial characteristics, and endocrinological follow-up data are presented. The data show a small incidence of side effects due to our therapeutic strategy.

MATERIALS AND METHODS

Sample Population

TranssexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients were seen by the authors in the Endocrinological Outpatient Clinic of the Max-Planck-Institute between 1991 and 1995 inclusively. During that time 129 patients were referred to us. For the purpose of the present study we reviewed the files of these patients and developed a questionnaire for personal data. The patients were also interviewed. Of the 129 patients treated, 88 (46 M-to-F and 42 F-to-M) provided us with personal information and were therefore included in the present study, 41 patients either refused to take part in the investigation or their addresses could not be ascertained. A complete history for controlled variables and treatment schedules was obtained besides the personal data. Physical examinations were performed regularly.

Cross-Gender Hormone Therapy

The aim of cross-gender hormone therapy in transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients is an assimilation of secondary sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. characteristics to the desired sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. as quickly as possible by administration of decreased doses of specific hormone recombinants in consecutive time intervals (steps) after beginning therapy. For this purpose F-to-M transsexuals were treated with a 250-mg depot of testosterone applied intramuscularly. Injection intervals varied between 2 weeks in the beginning to 3 to 4 weeks later on. Optimal lifelong therapy was designed individually by regular screening of serum testosterone, while serum estrogen levels were decreasing. Cross-gender hormone therapy for M-to-F transsexuals is more complex. Testosterone synthesis was decreased effectively by application of the antiandrogen cyproterone acetate. In the beginning of therapy we administered a daily dose of 100 mg orally, slowly adapting it to falling serum testosterone levels. Estrogens usually were administered in a two-phase regimen. High-dose pharmacological estrogen was given in the beginning of therapy as an intramuscular depot, generally every 2 weeks. Optimal individual injection intervals were defined according to patient’s risk factors, side effects of therapy, and serum hormone levels in intervals of between 1 and 3 months. As soon as secondary sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. characteristics had fully developed, therapy was changed from the high-dose application to a lifelong low-dose estrogen substitution therapy. This also has to be carefully monitored and modified if necessary. Antiandrogen therapy at this point is no longer necessary. For more information concerning cross-gender hormone therapy forms, its risks and side effects, see Schlatterer et al., 1996.

Statistical Analysis

Since the majority of the variables considered in the study are of nominal or categorial data structure, analysis of contingency tables was basically used for evaluating the data at hand. Besides the frequency distributions of transsexuals within the levels (categories) of the various variables, tests of significance of the dependence of transsexuality and certain variables based on the chi-square statistic were performed. (Note: dependent upon the values of the cell frequencies the p values of the chi-square statistic were calculated either exactly or approximately with Monte Carlo simulations.) A nominal level of significance [Alpha] = 0.05 was accepted. Various tests of independence (or tests of homogeneity) were performed at a reduced level of significance (Bonferroni correction), in order to keep the Type I error less or equal to 0.05.

Results

Before dealing with the effects of cross-gender replacement therapy on endocrinological findings the psychosocial background, the medical and drug background as well as the age distribution within each transsexuality group was investigated. We proposed to compare our results with those obtained by other studies.

Endocrinological and Side Effects During Cross-Gender Hormone Therapy

The clinical data of our transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients are presented in Table IV (not shown). For 12.5% of our transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients, cross-gender hormone therapy at the time of completion of this study was no longer performed. The number of F-to-M transsexuals with no continued therapy was more than the M-to-F ones (M-to-F: 6.5%, F-to-M: 19.04%). The rest (approximately 80%) of our F-to-M transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients received an intramuscular testosterone application therapy (250 mg every 2-3 weeks). Among the 46 M-to-F patients 32% (i.e., 15 patients) were still in the high-dose pharmacological phase of treatment and received a combination therapy of high dose estrogens together with antiandrogens (estradiol 40-100 mg im every 2 weeks together with cyproterone acetate 10-100 mg daily) whereas 4% (i.e., 2 patients) received high-dose estrogen therapy with estradiol 80-100 mg every 2 weeks alone. Of the M-to-F patients 22% still needed antiandrogen therapy when reducing the estrogen doses to 2-8 mg estradiol daily. In 30% of these patients testosterone serum levels had dropped so far that a combination therapy was pointless. They were administered estradiol 2-8 mg daily alone. For different reasons a minority of 2% of our M-to-F transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients received therapy with natural, unconjugated estrogens. The same number of patients was administered a combination of 2 mg cyproterone acetate and 35 microgram ethinylestradiol.

Under the hormone therapy 26% of the M-to-F transsexuals showed no side effects, whereas the number of F-to-M transsexuals without side effects was significantly higher (42%). Although some of our patients showed more than one side effect, we present in Table IV (not shown) the absolute frequency for the incidence of single side effects only. The most common side effect observed by the M-to-F patients was the development of hyperprolactinemia: 24 M-to-F transsexuals showed this symptom and in 4 we also found transient elevated levels of prolactin. These 4 patients performed mechanical compression of their breasts. The nonpersisting elevation of prolactin levels could be traced to this manipulation procedure of the breast. The incidence for transient hyperprolactinemia with normalizing levels of prolactin after dose adjustment was in the range of those found in studies already performed for estrogen-treated M-to-F transsexuals. On the other hand we detected no prolactinoma as described by other authors (Asscheman et al., 1988, 1989; Kovacs et al., 1994; Gooren et al., 1980). The portion of patients developing galactorrhea (5/40 [congruent] 13%) was lower in our study than the corresponding one found by Futterweit (1980). None of our patients developed deep vein thrombosis or embolism during cross-gender hormone therapy performed in our clinic. These side elects are the most severe ones during estrogen therapy and have been seen in many patients (Fortin et al., 1984; Lehrman, 1976). One of our M-to-F patients suffered from lilac vein thrombosis following surgery, another from deep vein thrombosis before starting therapy. Here it was not clear if the patient self-administered high doses of estrogens without medical control. One patient suffered from lung embolism before starting therapy. Here self-administration of estrogens was also difficult to evaluate. One patient suffered from severe varicosis. Therefore in his case we administered very low doses of estrogens under permanent control of blood-clotting parameters. This therapeutic compromise was performed as an exception, because the patient, who proved to be a serious and reliable partner for hormone therapy, insisted on estrogen administration. A closer examination of blood-clotting parameters as a risk assessment for thromboembolic complications (data not shown) revealed for 11 patients 1 single case of pathologically altered parameters under high-dose estrogen therapy. For this purpose we analyzed the prothrombin time, partial thromboplastin time (PTT), antithrombin III, protein C antigen, functional protein C, protein S antigen and APC-resistance.

Interestingly cross-gender hormone therapy had an influence on erythropoesis. In 15 examined estrogen-treated M-to-F transsexuals we found a decrease of hemoglobin compared to levels of women. In 5, F-to-M transexual patients testosterone treatment induced an increase of hemoglobin to levels normally seen in biological men . These changes correspond to the effects of androgens on erythropoesis as described by Kennedy and Gilbertsen (1957). This finding has been tried with varying success as a therapeutic approach for different diseases (Fried et al., 1973, Alexanian, 1969; de Gowin et al., 1970). In view of the erythropoetic effect of androgens, chronic respiratory disorders like emphysema and bronchial asthma are relative contraindications to cross-gender hormone therapy, particularly in heavy smokers.

In the group of F-to-M transsexuals, 3 patients suffered from persistent bleeding which ceased after the application of a high-dose gestagen between the testosterone applications. Three patients also reported concentration and/or sleep problems. Development of acne was seen in 4 patients. In F-to-M transsexuals, acne is one of the most common side effects observed, which often has to be treated with antibiotics (Schlatterer et al., 1996). In the group of M-to-F transsexuals, 2 patients suffered from severe headaches accompanying estrogen medication. For both patient groups (M-to-F and F-to-M transsexuals) a transient increase of liver enzymes was observed, similar to that described by (Meyer et al., 1986; Asscheman et al., 1989). After further diagnostic procedures (screening for hepatitis B and C antigens, ultrasonography of the liver), followed by adjusting and reducing sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. hormone doses, these changes in transaminases were no longer detected.

Long-term follow-up studies of cross-gender hormone-treated transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients have not been performed. Interesting objectives would be a systematic evaluation of prevalence of neoplasia and the investigation of an influence of cross-gender hormonesChemical substances that control and regulate the activity of certain cells or organs; see also: sex hormones. on the cardiovascular system. Single case reports of breast cancer in M-to-F transsexuals have been reported previously (Pritchard et al., 1988; Symmers, 1968). Effects of estrogens as part of oral contraceptives on the cardiovascular system are already known (Stadel, 1981; Hannaford et al., 1994; Glashan and Robinson, 1981; Biller and Saver, 1995; Goh et al., 1995; Damewood et al., 1989; de Marinis and Arnett, 1978).

Discussion

In the last 5 years we have established a cross-gender hormone substitution model for our endocrinological outpatient clinic, embedded in a multistep treatment concept for the transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patient (Schlatterer et al., 1996). Here we present data, summarizing our experiences with this therapy. We are by no means certain that our sample of transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients is complete and representative enough to carry out reliable epidemiological calculations. Our findings therefore should be regarded as estimates for an overview of the patient’s personal background, endocrinological findings, and the outcome of sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. reassignment.

Comparing our findings with others published so far, we first evaluated the psychosocial background (age distribution, marital status, number of children, occupational status, nicotine and alcohol consumption, family background) of our patients as well as the patient’s anamnesis. For the most part psychosocial variables of the two groups of our transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients did not differ significantly (see Table I-III – not shown), but these results compared to those obtained by other studies reveal some discrepancies. With regard to marital status (Table I – not shown) the two groups did not show homogeneity in the frequency distribution ([[Chi].sup.2]-test, p [less than] 0.05). Considerably more M-to-F than F-to-M transsexuals live in marriage, but here also the rate of divorce is higher. Data to date present controversial findings for this feature. Our findings confirm the reports of Hoenig and Kenna (1973) and Kockott and Fahrner (1988). Concerning occupational status, the F-to-M patients show employment patterns similar to M-to-F transsexuals. There are some differences in the frequencies of the single occupational status levels, but their values did not reach statistical significance: 8.7% of our M-to-F patients have already retired. The unemployment rate for F-to-M transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients in our study is higher than that for M-to-F transsexuals. This is in contrast to the findings of Tsoi (1992). In the group of F-to-M transsexuals more patients were still in school, apprenticeship, or visited university than in the group of M-to-F transsexuals. Tsoi (1990) has described for Singapore a lower incidence for M-to-F transsexuals to be in higher occupational classes than F-to-M, due to the fact that many M-to-F transsexuals take up service and entertainment jobs which can be graded as skilled or semiskilled.

One parameter that differs significantly from the studies published is the number of siblings. In our sample as many transsexuals have siblings as those having none, in contrast to Dixen et al. (1984), who published an incidence of being the only child of approximately 12%. In the transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients’ parents a high history of psychiatric disorders has been described by Dixen et al., which could not be confirmed by us. We found a weak occurrence of endocrinopathies, cardiovascular problems, neoplastic, and psychiatric-neurological disorders in the parents. Approximately 50% of the M-to-F transsexuals and 30 % of the F-to-M transsexuals show further disorders (see Table II – not shown). Endocrinopathies and psychiatric problems are the most frequent disorders, followed by diseases affecting the cardiovascular system, dermatological disorders, and chronic infectious diseases. The relatively high incidence of psychiatric history is consistent with the literature and can be interpreted as evidence of an extreme dissatisfaction that the patients experience in their current, unaccepted gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
(Fleming et al., 1981; Pauly 1974).

Previous studies showed a significant number (50%) of associated endocrinopathies in F-to-M transsexuals (Futterweit, 1980). The incidence of chronic infectious diseases like hepatitis B and C as well as HIV infection might possibly be related to the sexual behavior these patients show before their disorder is accepted and treated (same-sex partners, sometimes in a homosexual environment with an increased incidence of sexually transmittable infectious diseases). To a minor extent other disorders have been observed. Approximately 18% of our patients, independent of gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
, regularly took other drugs beside cross-gender hormonesChemical substances that control and regulate the activity of certain cells or organs; see also: sex hormones., analgesics, psychopharmaceutics, and endocrinological agents are the most frequent. Slightly fewer F-to-M than M-to-F transexuals smoke, whereas the alcohol consumption in F-to-M transsexuals is significantly higher.

The two transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. groups showed significant discrepancies both in the age of diagnosis and in the age at beginning cross-gender hormone therapy ([[Chi].sup.2]-test, p [less than] 0.05). Most of the patients are diagnosed as transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. between the age of 21 and 30 years, independently of the biological gender• However gender is far more complicated. It is the complex interrelationship between an individual’s sex (gender biology), one’s internal sense of self as male, female, both or neither (gender identity) as well as one’s outward presentations and behaviours (gender expression) related to that perception, including their gender role. Together, the intersection of these three dimensions produces one’s authentic sense of gender, both in how people experience their own gender as well as how others perceive it.
• Gender is expressed in terms of masculinity and femininity. It is largely culturally determined and is assigned at birth based on the sex of the individual. It affects how people perceive themselves and how they expect others to behave.
• Socially and culturally constructed roles, behaviours, expressions and identities of girls, women, boys, men, and trans people.
. About 16% of M-to-F transsexuals are diagnosed older than 41 years (Table III – not shown). Many of the patients were referred to our clinic by the psychiatrist, followed by the neurologist, the general practitioner, and the internist. As many patients are member of patients’ organizations as not.

Hormone replacement therapy was started in our clinic with the same age distribution. The kind of cross-gender hormone therapy was adjusted according to the side effects observed. The incidence of hyperprolactinemia we found in estrogen-treated F-to-M transsexuals (Table IV – not shown) lies in the range of studies published before (Asscheman et al., 1988, 1989), whereas the number of patients developing galactorrhea was significantly lower in our patients. None of our patients suffered from a prolactin-producing pituitary adenoma. The incidence of thromboembolic events during cross-gender hormone treatment in our patients was zero. Changes in haematological parameters were observed under cross-gender hormone therapy. Transient rises in transaminases occurred at a similar frequency as described by other authors (Asscheman et al., 1989; Meyer et al., 1986).

The follow-up of these patients for completed sex reassignment surgerySee gender-affirming surgery. revealed an incidence of problems due to surgery of approximately 20%. Wound healing and urological problems proved to be the most frequent. M-to-F transsexuals were affected slightly more than F-to-M patients, despite better surgical chances for this group. Less than 5% of our transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients refused any surgical intervention. These numbers were independent of biological sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy..

With this follow-up study we have been able to demonstrate a low incidence of severe complications occurring due to a specific cross-gender hormone replacement therapy in 88 transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients. Long-term follow-up studies have to be carried out to evaluate further risks of cross-gender hormone replacement therapy like the possible development of neoplasia or long-term effects leading to cardiovascular diseases. Cases of ischemic cerebrovascular diseases accompanying infertility therapy or cross-gender hormone replacement therapy, as performed in transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients, have been reported (Biller and Saver, 1995). Influences of estrogen and testosterone therapy on lipid/lipoprotein profiles are also described (Goh et al., 1995; Damewood et al., 1989). The design and realization of such studies could help to further improve therapy strategies for transsexuals.

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• Goodwin, W. E., and Cummings, R. H. (1984). Squamous metaplasia of the verumontanum with obstruction due to hypertrophy: long-term effects of estrogen on the prostate in an aging male-to-female transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body.. J. Urol. 131: 553-554.
• Gooren, L. (1990). The endocrinology of transsexualism• This term is used to describe a person who has “transitioned”, or is in the process of “transitioning”, or intends to transition from male to female or female to male. For a transsexual person, the process of “transitioning”, may involve a variety of treatments including: hormone therapy, surgery and hair removal. People who have transitioned do not necessarily identify as trans any longer; they may identify as simply a man or a woman. Some transsexual people may not transition due to family or other social constraints.
  • When people complete their transition, they may no longer regard themselves as part of the trans umbrella. They might consider having been transsexual to just be an aspect of their medical history which has now been resolved and so is no longer an issue in their life. In such cases, they simply describe themselves as men or as women and it is most disrespectful to insist on calling them trans, transgender or transsexual against their wishes.
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• Gooren, L. J. G., van der Veen, E. A., and van Kessel, H. (1980). Modulation of prolactin secretion by gonadal steroids in men. In: MacLeod, R. M., and Scapagnini, U. (eds.), Central and Peripheral Regulation of Prolactin Function, Raven Press, New York, pp. 373-375.
• Green, R. (1966). Mythological, historical, and cross-cultural aspects of transsexualism• This term is used to describe a person who has “transitioned”, or is in the process of “transitioning”, or intends to transition from male to female or female to male. For a transsexual person, the process of “transitioning”, may involve a variety of treatments including: hormone therapy, surgery and hair removal. People who have transitioned do not necessarily identify as trans any longer; they may identify as simply a man or a woman. Some transsexual people may not transition due to family or other social constraints.
  • When people complete their transition, they may no longer regard themselves as part of the trans umbrella. They might consider having been transsexual to just be an aspect of their medical history which has now been resolved and so is no longer an issue in their life. In such cases, they simply describe themselves as men or as women and it is most disrespectful to insist on calling them trans, transgender or transsexual against their wishes.
  . In Benjamin H. The TranssexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. Phenomenon. The Julian Press, New York.
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  • When people complete their transition, they may no longer regard themselves as part of the trans umbrella. They might consider having been transsexual to just be an aspect of their medical history which has now been resolved and so is no longer an issue in their life. In such cases, they simply describe themselves as men or as women and it is most disrespectful to insist on calling them trans, transgender or transsexual against their wishes.
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• Kovacs, K., Stefaneanu, L., Ezzat, S., and Smyth, H. S. (1994). Prolactin-producing pituitary adenoma in a male-to-female transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patient with protracted estrogen administration. Arch. Pathol. Lab. Med. 118: 562-565.
• Lehrman, K. L. (1976). Pulmonary embolism in a transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. manA human being who self-identifies as a man, based on elements of importance to the individual, such as gender roles, behaviour, expression, identity, and/or physiology. taking diethlstilbestrol. J. Am Med. Assoc. 235: 532-533.
• Meyer, W. J., Webb, A., and Stuart, C. A. (1986). Physical and hormonal evaluation of the transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patient. A longitudinal study. Arch. SexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy.. Behav. 15: 121-138.
• Pauly, I. (1965). MaleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). psychosexual inversion: Transsexualism• This term is used to describe a person who has “transitioned”, or is in the process of “transitioning”, or intends to transition from male to female or female to male. For a transsexual person, the process of “transitioning”, may involve a variety of treatments including: hormone therapy, surgery and hair removal. People who have transitioned do not necessarily identify as trans any longer; they may identify as simply a man or a woman. Some transsexual people may not transition due to family or other social constraints.
  • When people complete their transition, they may no longer regard themselves as part of the trans umbrella. They might consider having been transsexual to just be an aspect of their medical history which has now been resolved and so is no longer an issue in their life. In such cases, they simply describe themselves as men or as women and it is most disrespectful to insist on calling them trans, transgender or transsexual against their wishes.
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• Pauly, I. B. (1968). The current status of the sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. change operation. J. Nerv. Ment. Dis. 147: 460-471.
• Pauly, I. B. (1974). FemaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus). transsexualism• This term is used to describe a person who has “transitioned”, or is in the process of “transitioning”, or intends to transition from male to female or female to male. For a transsexual person, the process of “transitioning”, may involve a variety of treatments including: hormone therapy, surgery and hair removal. People who have transitioned do not necessarily identify as trans any longer; they may identify as simply a man or a woman. Some transsexual people may not transition due to family or other social constraints.
  • When people complete their transition, they may no longer regard themselves as part of the trans umbrella. They might consider having been transsexual to just be an aspect of their medical history which has now been resolved and so is no longer an issue in their life. In such cases, they simply describe themselves as men or as women and it is most disrespectful to insist on calling them trans, transgender or transsexual against their wishes.
  I and II. Arch. SexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. Behav. 3: 487-526.
• Pritchard, T. J., Pankowsky, D. A., Crowe, J. P., and Abdul-Karim, F. W. (1988). Breast cancer in a male-to-female transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body.. A case report. J. Am. Med. Assoc. 259: 2278-2280.
• Schlatterer, K., von Werder, K., and Stalla, G. K. (1996). Multistep treatment concept of transsexualThis is typically used to describe people who identify as transgender who are transitioning toward the gender with which they identify. This may include socially presenting (e.g., clothing, hair, mannerisms, overall gender expression) as the gender with which they identify, or it may include more extensive changes like taking hormones and/or surgical procedures to modify their body. patients. Exp. Clin. Endocrinol. (in press).
• Stadel, B. V. (1981). Oral contraceptives and cardiovascular disease. New Engl. J. Med. 305: 612-618, 672-677.
• Symmers, W. C. (1968). Carcinoma of the breast in trans-sexual individuals after surgical and hormonal interference with the primary and secondary sexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy. characteristics. Br. Med. J. 2: 83-85.
• Tsoi, W. F. (1990). Developmental profile of 200 maleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). and 100 femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus). transsexuals in Singapore. Arch. SexBiological attributes and legal categories used to classify humans as male, female, intersex or other categories, primarily associated with physical and physiological features including chromosomes, genetic expression, hormone levels and function, and reproductive/sexual anatomy.. Behav. 19: 595-605.
• Tsoi, W. F. (1992). MaleA sex, usually assigned at birth, and based on chromosomes (e.g. XY), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. penis, testicles). and femaleA sex, usually assigned at birth, and based on chromosomes (e.g. XX), gene expression, hormone levels and function, and reproductive/sexual anatomy (e.g. vagina, uterus). transsexuals: A comparison. Singapore Med. J. 33: 182-185.