New Research on Gender-Affirming Testosterone and Fertility

Mouse model of gender-affirming testosterone treatment and fertility finds decrease in egg yield but not quality

12:00 PM

Jump to Transcript

Evidence can help inform fertility care for transgender and gender diverse people who wish to become parents. Visit Health Lab to read the full story.

Transcript

Host: 

Welcome to Health Lab, your destination for news and stories about the future of healthcare. Today: New research can help inform fertility care for transgender and gender diverse people who wish to become parents.

Although transgender and gender diverse young adults demonstrate a high interest in parenting, less than 20% of transgender and nonbinary individuals in the United States are parents.

Transgender and gender diverse people who wish to become parents face barriers including discrimination in the health care setting, access to high quality fertility care and high cost as fertility care is not typically covered by public or private insurers.

Beyond logistic barriers to receiving fertility treatment, the potential stress of halting gender-affirming hormones before treatment poses an additional challenge.

Organizations recommend doctors council patients who are beginning gender-affirming treatment about fertility preservation to avoid pausing hormones later.

However, freezing eggs or sperm is often cost prohibitive for an 18 or 19-year-old adult patient beginning gender-affirming hormones.

The current recommendation is for patients to stop taking gender-affirming hormones for up to a three month “washout period” before in vitro fertilization, commonly known as IVF, says Molly Moravek, M.D, M.P.H., MSCI, a reproductive endocrinologist at Michigan Medicine.

“It’s unfair that we are advising people to make life changing interventions by spending thousands of dollars to freeze eggs or halting testosterone for three months before IVF out of fear that testosterone treatment might affect their fertility,” said Moravek.

“We worry testosterone might affect their fertility outcome, but we don’t have any evidence for that claim.”

To remedy this, Moravek led a University of Michigan team with Ariella Shikanov, Ph.D., and Vasantha Padmanabhan, Ph.D., to investigate how gender-affirming testosterone treatment affected IVF outcomes using a mouse model.

Researchers divided genetically identical female mice into four treatment groups: a control implant, a testosterone implant, a control implant washout and a testosterone implant washout.

The first two groups underwent ovarian stimulation for egg collection with hormone implants in place while the washout groups had the hormone implant removed for two weeks before ovarian stimulation.

Eggs were then collected, fertilized and cultured in vitro for early embryonic stages.

The experiment was conducted twice with testosterone implants in place for six or 12 weeks to represent short and long-term testosterone exposure.

The researchers found that testosterone treatment decreased egg yield without affecting quality.

For the short-term testosterone treatment group with a two-week washout, IVF outcomes were fully recovered to the level of controls.

However, IVF outcomes were not fully recovered for the long-term testosterone treatment group.

“In mice, we’re seeing that you may get less eggs with testosterone treatment, but those eggs are fine and still create normal embryos that become live born offspring,” said Moravek.

The researchers plan to investigate whether there is a medication that can clear out the eggs to hasten the washout period.

Moravek also plans to study multiple generations of mice to determine whether the offspring of gender-affirming testosterone treated parents experience any reduced fertility or metabolic effects.

As evidence builds, this information can help inform conversations between doctors and patients when deciding whether to halt gender-affirming testosterone treatment before IVF.

“Some patients are comfortable halting gender-affirming testosterone. For others, it can be very distressing,” said Moravek.

For the subset of patients who would be distressed by stopping gender-affirming testosterone, ovarian reserve – or the number of eggs remaining in the ovaries – can help direct the conversation, says Moravek.

The egg loss may not be a concern for a patient with a great ovarian reserve but for a patient with a low ovarian reserve, it will be important to discuss the pros and cons of continuing gender-affirming testosterone.

“We owe it to our patients to have data to back up decisions before we tell them to do these expensive and emotionally taxing procedures,” said Moravek.

For more on this story and others like it, visit michiganmedicine.org/health-lab. Health Lab is a part of the Michigan Medicine Podcast Network and is produced by the Michigan Medicine Department of Communication. You can subscribe to Health Lab wherever you listen to podcasts.


More Articles About:

Healthcare Transgender fertility reproductive endocrinology podcast Michigan Medicine
Health Lab Podcast in brackets with a background with a dark blue translucent layers over cells

Health Lab Podcast

Listen to more Health Lab podcasts - a part of the Michigan Medicine Podcast Network.

Featured News & Stories

Well-Being at Michigan Medicine with Dr. Elizabeth Harry
Well-Being at Michigan Medicine

Rethinking care: How ‘de-implementation’ can improve quality and reduce burnout

In this episode of Well-Being at Michigan Medicine with Dr. Elizabeth Harry, Dr. Eve Kerr explores the concept of de-implementation—scaling back unnecessary tests, treatments, and administrative hurdles. Kerr shares how eliminating low-value practices can reduce clinician overload, lower patient costs, and improve overall health outcomes. Discover how both healthcare organizations and local frontline teams can foster a culture of high-value care by eliminating outdated processes.
The Fundamentals Podcast Hero Card Final 1800 x 1350
The Fundamentals

The Questions That Shape the Future of Medicine

On this episode of The Fundamentals, we talked to Dr. Thomas J. Wang, dean of the University of Michigan Medical School, about the fundamental questions that have shaped his career and continue to drive biomedical research. Dean Wang discusses his work in cardiovascular research, the enduring impact of the Framingham Heart Study, the potential of AI and emerging health data, and the importance of collaboration between academia and industry. He also shares advice for the next generation of scientists and physicians and explains why sustained investment in biomedical research is essential to improving human health.
egg freezing in lab
Health Lab

Egg freezing: What women should know about fertility preservation

An egg-freezing question and answer article with two Michigan Medicine experts.
Health Lab Podcast in brackets with a background with a dark blue translucent layers over cells
Health Lab Podcast

The Kidney Warning Signs You’re Missing— And Why Waiting is Dangerous

To celebrate the 10 year anniversary, Health Lab hosted its the first Health Lab Live Show, which brought two Health Lab articles to life by interviewing experts live on stage in front of a live audience while deep diving into trending health and wellness topics. Julie Wright, M.D., a nephrologist, talks about the silent symptoms you’d never suspect, why most people don’t catch issues until it’s too late, and what you can do today to get ahead of any issues. She even says you might be able to prevent it if you spot concerning bloodwork early.
A logo of US News and World Report honor roll 2026-2027 with university of Michigan medical campus.
News Release

University of Michigan Health named Michigan’s top hospital, earns spot on U.S. News honor roll

University of Michigan Health in Ann Arbor ranks among the nation’s best — and is the top hospital in Michigan — according to the U.S. News & World Report Best Hospitals rankings for 2026-2027.
Health Lab Podcast in brackets with a background with a dark blue translucent layers over cells
Health Lab Podcast

Cyclospora: What to Know About the Parasite Sweeping the Nation

Key tips for getting through an outbreak if you or your loved ones get sick.