Clinical trial NCT03789331: Anogenital Distance Differences Between Transgender Males and Female Individuals
Official title: Anogenital Distance Differences Between Transgender Males and Female Individuals
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Sexual Orientation Conflict Disorder
Keywords: transgender males
anogenital distance
Lead sponsor: Uludag University
Sponsor class: OTHER
First posted: 2018-12-28
Enrollment: 150
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: The study population will be healthy transgender male individuals whose gender identity (Male) are different from their birth-assigned sex (Female). These individuals are healthy biologically female persons and want to change their gender to male status. In Turkey, if a woman wants to change her gender, she has to bring a lawsuit against the birth registration office to change her gender to male status. Medico-legal assessments then have to be made at a tertiary gynecological center through the court. The participants will be invited to the study at the time of medico-legal evaluation before the sex reassignment surgery.

Brief summary: This study evaluates the anogenital distance measurement differences between transgender male individuals and normal healthy female individuals. Half of the participants will be selected from the men with a masculine gender identity who were assigned female sex at birth (Woman who wanted to be a man). Transgender men will be evaluated with the vaginal examination, and anogenital distance will be measured at the time of gynecological medico-legal evaluation before the sex reassignment surgery. While the other half of the participants will be selected from healthy female individuals, ordinary healthy women will be selected from patients who come to the gynecology clinic for another reason (Women with normal sexual orientation).

Detailed description: There is considerable evidence in human beings and in animal models supporting that anogenital distance as a sensitive biomarker of prenatal androgen reflection of reproductive health and sexual orientation. Anogenital distance is approximately twice as long in male animals compared to female animals, and it is routinely used to determine the natal or birth-assigned sex.

Studies have shown alterations in anogenital distance associated with reproductive health and sexual orientation. For instance, shorter anogenital distance has been reported in boys with hypospadias and cryptorchidism. Men with reduced testicular volume have significantly shorter anogenital distance compared with controls. Increased anogenital distance has been indicated in girls with congenital adrenal hyperplasia.

The investigators hypothesized that a prenatal pathological androgenic environment, resulting in a longer anogenital distance, will be able to be associated with a higher risk of sexual orientation disorders like transsexualism. This cross-sectional study aimed to assess the anogenital distance measurement differences between transgender male persons and normal healthy female individuals.

Eligibility criteria: Inclusion Criteria:

* Individuals who are 18-50 years old.
* Healthy transgender male individuals whose gender identity (Male) are different from their birth-assigned sex (Female). The participants will be invited to the study at the time of medico-legal evaluation before the sex reassignment surgery.

Exclusion Criteria:

* Individuals who are older than 50 (People older than 50 cannot change their gender legally in Turkey).
* Other sexual orientation disorders. (Lesbian, Gay, Bisexual, Queer, Intersex, or Asexual persons)

Primary outcomes:
measure: Anogenital Distance (Anus-Clitoris)
timeFrame: 1 hour
measure: Anogenital Distance (Anus-Posterior Fourchette)
timeFrame: 1 hour
Secondary outcomes:
measure: Anti-Mullerian Hormone (AMH) level measurement
timeFrame: 8 hours
measure: FSH (Follicle-stimulating hormone), LH (Luteinizing hormone), Estradiol, and Testosteron level measurements
timeFrame: 8 hours
Other outcomes:
Locations:
city: Bursa
country: Turkey
facility: Uludag University Hospital, Department of Obstetrics and Gynecology
state: Ozluce
Study officials:
affiliation: Uludag University, Department of Obstetrics and Gynecology
name: Adnan Orhan, M.D.
role: STUDY_DIRECTOR
References:
citation: Wu Y, Zhong G, Chen S, Zheng C, Liao D, Xie M. Polycystic ovary syndrome is associated with anogenital distance, a marker of prenatal androgen exposure. Hum Reprod. 2017 Apr 1;32(4):937-943. doi: 10.1093/humrep/dex042.
citation: Sanchez-Ferrer ML, Mendiola J, Hernandez-Penalver AI, Corbalan-Biyang S, Carmona-Barnosi A, Prieto-Sanchez MT, Nieto A, Torres-Cantero AM. Presence of polycystic ovary syndrome is associated with longer anogenital distance in adult Mediterranean women. Hum Reprod. 2017 Nov 1;32(11):2315-2323. doi: 10.1093/humrep/dex274.