What is testosterone studying for transgender men and reproductive health?

This clinical trial studies how testosterone therapy affects reproductive hormones and menstrual cycles in transgender men. Researchers want to understand the impact of testosterone on hormone secretion and menstrual disruption. The study is led by the University of California, San Diego. Participants can expect detailed hormone monitoring and clinical evaluations throughout the trial.

Who may be eligible for this transgender and reproductive health clinical trial?

Adults aged 18 to 35 who identify as transgender men or cisgender females with regular menstrual cycles may be eligible. Participants must be willing to comply with study procedures and not have certain health conditions or recent hormone treatments. Please review eligibility criteria for more details.

Is there any cost to participate in this transgender and reproductive health clinical trial?

Study-related care, including the study drug and all trial visits, is provided at no cost. However, personal travel expenses may vary and are not guaranteed to be covered. Participants should plan accordingly for any travel or related costs.

Actively Recruiting

Phase 4

Age: 18Years - 35Years

FEMALE

Healthy Volunteers

ID07092527

Effects of Testosterone Therapy on Reproductive Hormones and Menstrual Patterns in Transgender Men and Cisgender Females Aged 18 to 35

Led by University of California, San Diego · Updated on 2026-01-15

Participants Needed

Research Sites

2 weeks

Total Duration

AI-Summary

What this Trial Is About

Researchers are studying the effects of male-level testosterone on the reproductive hormone system in healthy females without polycystic ovary syndrome. The study focuses on transgender men beginning testosterone replacement therapy TRT and compares them to cisgender females with regular menstrual cycles. The goal is to understand how testosterone impacts ovarian hormones, pituitary hormone release, and menstrual patterns, addressing a gap in knowledge about menstrual changes during TRT. Participants include transgender men or non-binary individuals starting weekly testosterone injections for gender-affirming care, and a control group of cisgender females who do not receive treatment. The study tracks hormone levels and reproductive function over about seven months, with clinical and ultrasound evaluations performed periodically to monitor changes. During the study, participants will undergo blood tests to measure reproductive hormones like luteinizing hormone, follicle-stimulating hormone, estradiol, and testosterone. Uterine bleeding patterns and hormone secretion patterns will be closely observed. The research team will also perform ultrasound scans and clinical assessments to track reproductive health. The total participation lasts around seven months, during which hormone activity and menstrual changes are carefully evaluated.

CONDITIONS

Brief Title

Androgen Effects on the Reproductive Neuroendocrine Axis, 2025 Version

How This Trial Compares With Other Options

This table compares participation in this trial with other options available for this condition. The information is drawn from published research and the trial’s study details and is provided for educational purposes only.

Factors	Transgender men/nonbinary individuals initiating testosterone	Cisgender females (no hormone intervention)
What it is	Weekly injectable testosterone cypionate administered to transgender men and nonbinary adults seeking gender-affirming hormone therapy.	Cisgender female adults matched by age and reproductive cycle, receiving no hormone intervention.
Role in this study	Evaluates how initiating testosterone therapy affects reproductive hormones and menstrual cycles in transgender men and nonbinary individuals.	Used as a reference group to compare natural hormonal fluctuations and menstrual patterns without hormone therapy.
Primary use	Masculinizing hormone therapy provided for gender affirmation in transgender and nonbinary adults.	No hormonal intervention, representing endogenous reproductive and hormonal function.
How it is given or performed	Testosterone cypionate is administered by weekly intramuscular or subcutaneous injections.	No medication; participants continue their natural menstrual cycles without any hormonal treatment.
Evidence status	Testosterone therapy is supported by published studies and clinical guidelines for masculinization but long-term reproductive hormone and fertility effects are still under investigation.	Represents typical reproductive hormone profiles and menstrual function as the physiologic baseline for comparison.
Important limitations	While testosterone therapy is widely used, high-quality evidence regarding its effects on ovulation, menstruation, and future fertility is limited, with ongoing research to clarify reproductive risks and benefits.	Control group data provide a reference for normal hormone variation but cannot account for all lifestyle, health, or demographic influences.

Disclaimer: This comparison is created with the help of artificial intelligence(AI) and may contain errors or missing information. It is not medical advice and does not mean one option is better or safer than another. Clinical trials are still being studied, and joining a trial is your choice. Please consult your healthcare professional before making any decisions.

Who Can Participate

Age: 18Years - 35Years

FEMALE

Healthy Volunteers

Eligibility Criteria

You may qualify if you...

Signed and dated informed consent form
Willingness to comply with all study procedures and availability for the study duration
Age between 18 and 35 years
For transgender/non-binary group: planning to start testosterone therapy and history of regular menstrual cycles every 24-35 days before therapy
For cisgender female group: regular menstrual cycles every 24-35 days

You will not qualify if you...

Pregnant or breastfeeding within two months prior to enrollment
Incarcerated or institutionalized with known cognitive impairment
Hemoglobin less than 11 gm/dl at screening
Weight less than 110 pounds
Body mass index less than 18 or greater than 35
Current endocrine diseases such as untreated thyroid problems, pituitary or adrenal disease, polycystic ovary syndrome, or androgen-producing tumors
Recent pregnancy within two months prior to enrollment
Diabetes or kidney, liver, or heart disease
History of oophorectomy or hysterectomy
History of radiation or surgery involving brain or pelvic organs
Current use of medications affecting reproductive hormones, including contraceptives, androgens, estrogens, progestins, GnRH antagonists, insulinomimetics, or metformin
Prior use of testosterone therapy

Your Study Journey

Screening

Duration - 2 to 4 weeks

Participants are screened for eligibility to participate in the trial.

1 visit (in-person)

Treatment

Duration - Approximately 7 months

Participants in the transgender men group receive weekly testosterone injections as part of gender-affirming care. Cisgender female participants do not receive treatment but are observed as a control group.

Weekly visits for up to 7 months

Monitoring

Duration - Approximately 7 months

Participants undergo periodic clinical and ultrasonographic evaluations to study reproductive hormone secretion and menstrual patterns during the study.

Periodic visits during the treatment period