Anogenital Distance Differences Between Transgender Males and Female Individuals

• Conditions: Sexual Orientation Conflict Disorder
• Interventions: Other: Anogenital distance measurement

• Registration Number: NCT03789331
• Lead Sponsor: Uludag University

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.

Study Timeline

• Study First Submitted: 2018-12-26
• Study First Submitted QC: 2018-12-26
• Study First Posted: 2018-12-28
• Status Verified: 2019-03
• Last Update Submitted: 2019-03-31
• Study Start: 2019-04-01
• Last Update Posted: 2019-04-02
• Primary Completion: 2020-02-15
• Study Completion: 2020-03-15

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: Female
• Target Recruitment: 150

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)

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Normal healthy female individuals	Anogenital distance measurement	* Group Description: Healthy women with normal sexual orientation. * Intervention: (The same) Anogenital distance measurement with a digital caliper in centimeters in the lithotomy position.
Transgender Male individuals	Anogenital distance measurement	* Group Description: This group consists of transgender male individuals who come to the gynecology clinic for medico-legal evaluation before the sex reassignment surgery. * Intervention: Anogenital distance measurement with a digital caliper in centimeters in the lithotomy position.

Primary Outcome Measures

Name	Time	Method
Anogenital Distance (Anus-Clitoris)	1 hour	Anogenital Distance (Anus-Clitoris) will be measured from the anterior clitoral surface to the centre of the anus with a digital caliper in centimeters.
Anogenital Distance (Anus-Posterior Fourchette)	1 hour	Anogenital Distance (Anus-Posterior Fourchette) will be measured from the posterior fourchette to the centre of the anus with a digital caliper in centimeters.

Secondary Outcome Measures

Name	Time	Method
Anti-Mullerian Hormone (AMH) level measurement	8 hours	All blood samples will be collected in the morning after the patient has fasted for at least 8 hours.
FSH (Follicle-stimulating hormone), LH (Luteinizing hormone), Estradiol, and Testosteron level measurements	8 hours	All blood samples will be collected in the morning after the patient has fasted for at least 8 hours.

Trial Locations

Locations (1)

Uludag University Hospital, Department of Obstetrics and Gynecology; 🇹🇷 Bursa, Ozluce, Turkey