Endocrine Abstracts

Background: The most significant hypotheses regarding biological causes of transsexualism are based on the role of environmental hormonal exposure on neural development.

Aim: This study was to analyse the baseline hormonal results in a population of transsexuals attending a single clinic to identify any abnormalities in hormone levels in these individuals.

Method: A retrospective cohort study was carried out using data collected from the clinical notes and MISIS database for patients booked to attend the clinic between 1st January 2003 and 31st December 2005. 191 patients were included in the study, with 161 of these being male-to-female and 30 being female-to-male. The levels of FSH, LH, Oestrogen and Testosterone were recorded, within a database, for each of these patients, and the number of normal and abnormal readings were counted. Chi Squared testing was then used to analyse these results to determine whether or not there was a significant difference to those expected within the general population.

Results: In Male-to-Female transsexuals a significant difference was found for LH, FSH, Oestrogen and Testosterone levels (P=0.001). The Oestrogen was higher than the normal range in all cases. LH and FSH were both twice as likely t o be low than high [LH6% low versus 14% high, FSH 14% low versus 27% high]. In female-to-male transsexuals a significant difference was found in LH, FSH and Oestrogen levels (P=0.001). Testosterone was raised in 12% (P=0.05).

Conclusion: Within this particular patient population is would appear that there are highly significant abnormalities within their hormone profiles which may play a role in the aetiology of their transsexualism. These patients would need to be investigated more closely in order to establish a mechanism by which these abnormal hormone levels may lead to the development of transsexualism, or whether these findings support any of the current theories.