Introduction to Testosterone and Female Fertility

Testosterone isn’t just a male hormone.  In fact, both men and women have testosterone in their bodies and it is an important part of both male and female fertility.  Long thought to be a detriment to female fertility and egg quality, new research on transgender fertility has shown this may not be the case.  Produced in the ovary, adrenal cortex, and placenta during pregnancy, testosterone is important for many things in women including a healthy sex drive and strengthening bones and muscles.  Testosterone can also be turned into estrogen, the main sex hormone in women.  In this article, we’ll help you understand testosterone’s role in female fertility as well as the clinical and societal impacts of testosterone and hormone therapy in relation to female fertility.  There’s a lot to go over so let’s dive right in.

The Biological Impact of Testosterone on Ovulation and Follicle Development

When you think of ovulation, testosterone isn’t the first hormone that usually comes to mind.  Ovulation is a reoccuring event and the phase of your menstrual cycle where an egg is released from the ovaries.  Previous lines of thought didn’t give enough credence to the role of androgens, but it turns out that they are necessary for normal ovarian function. 

During your menstrual cycle, follicle stimulating hormone (FSH) rises and helps to develop an ovarian follicle, which eventually houses an egg.  FSH also helps to initiate the production of estrogen, which supports the further development of the follicle and egg, while also thickening the uterine lining.  Next, luteinizing hormone (LH) surges and triggers the body to ovulate.  The whole process of ovulation involves the egg being released from the follicle and traveling down the fallopian tube towards the uterus.

Regardless of when you ovulate, your sex hormones follow a predictable path before ovulation and are one of the most accurate and fundamental signs of ovulation to track.  Mira’s digital fertility analyzer measures the numeric levels of fertility hormones (including LH and FSH) with a urine test allowing you to gain a detailed overview of your entire cycle and see your hormone levels in real time.  

New research from the University of Rochester School of Medicine and Dentistry suggests that androgens, especially testosterone, play more of a role than we thought.  Although the study was done on mice, it suggests that male hormones help drive follicle development which ultimately influences ovulation.  Androgens like testosterone are not only increasing follicle growth, but they’re ensuring follicles don’t die as well.  This is promising news for those who produce fewer follicles and have diminished ovarian reserve.  

Using testosterone to improve IVF outcomes has had limited results and can be controversial among fertility experts, but this research shows a promising new area to explore for enhancing fertility in those with diminished ovarian reserve.   

Factors Influencing Testosterone Levels in Women

Testosterone levels in women can be influenced by a number of factors and some people assigned female at birth have higher or lower levels of testosterone than others.  Low levels of testosterone can lead to symptoms such as sluggishness, mood swings, muscle weakness, fatigue, sleep disturbances, lack of concentration, reduced sex drive and sexual satisfaction, weight gain, hair thinning, fertility issues, irregular menstrual cycles, and vaginal dryness.  

There are a number of factors that can influence your testosterone level.  Testosterone levels naturally decrease as women age, especially after menopause.  Medications that manage menopause side effects, like oral estrogen, can also lower testosterone levels.  Other causes of low testosterone include ovary removal surgery, chemotherapy, and even eating disorders, like anorexia.  

For those taking testosterone as part of hormone therapy, it is a dose-dependent ovulation suppressant.  This means that if you take your dose as prescribed, it will stop ovulation.  Long thought to be a fertility killer by the medical community, new research out of Boston IVF on trans fertility has shown this is not the case.  Even if you’ve been taking testosterone for a long period of time, this study found no adverse effects from taking testosterone on egg quality and pregnancy outcomes.  

Testosterone and Sexual Function in Women

There’s a complex relationship between testosterone levels and female sexual function.  Although it plays a role in ovarian reserve, bone strength, and overall health, it’s also part of what drives female desire, sex drive, and sexual function.  In fact, according to the North American Menopause society, a dip in testosterone levels is likely responsible for our declining libido after menopause.  In premenopausal women, androgen deficiencies are much less explored and is an area ripe for more research.    

Testosterone supplementation (especially for low libido) is common in men, but more controversial in women given that there has been no research done on the long term effects.  Most women are prescribed testosterone formulations designed for men with dose modification, compounded therapies, or other “off-label” uses.  Testosterone also carries the risk of side effects like acne, and hair growth at the site, but also weight gain, hair loss, oily skin and mood changes just to name a few.  More research is needed to study the potential long term effects of testosterone supplementation in women.

How can I test Testosterone?

Testosterone is a blood test. You have two options to obtain results: 

• Clinical blood test from a vein,
• At-home finger-prick test, that is gaining popularity due to their convenience and privacy.

To get your free Testosterone results, you can use Mira Panorama Fertility Lab Test (US only).

It’s a quick and easy at-home finger-prick test that measures 5 hormones: not only Free Testosterone, but also AMH, fT4, Prolactin, and TSH. 

You will get 5 individual and personalized hormone reports with actionable steps to understand what your numbers mean for your ovarian reserve, thyroid function, menstrual cycle, hormonal balance, and fertility health.

Clinical and Societal Implications

Testosterone Therapy: Prospects and Concerns

Testosterone therapy in women can be a controversial topic.  It is a common prescription for men, but the success of treatment in women is questionable.  In fact, in the US, the Food and Drug Administration (FDA) has not approved testosterone replacement therapy for women and there are no formulations available with the correct dose for women.  Testosterone therapy is only recommended as treatment for hypoactive sexual desire disorder in postmenopausal women.  

Testosterone is being increasingly used for hormonal balance in pre and postmenopausal women.  Since androgens play an important role in so many systems and functions, testosterone therapy is usually prescribed for the benefit of sexual well-being, muscle mass, energy, bone health, and brain health.  When used appropriately the risks are minimal, but there are concerns about cardiovascular health and anyone undergoing testosterone therapy should be monitored regularly and have their levels checked.  No robust scientific studies have looked at potential lasting side effects or testosterone’s long-term safety in women but more research is being done in the area.

Testosterone therapy has long been used to help with gender transition in transgender men and gender nonbinary individuals.  The guidelines published by the Endocrine Society offer a full discussion of this treatment including the benefits and potential risks.       

Testosterone Therapy and Its Impact on Fertility

The science behind gender affirming hormonal treatments is quite new and there’s still much to learn, especially when it comes to fertility.  Although testosterone suppresses ovulation, it is not a form of birth control and you can still become pregnant while taking testosterone.

Unfortunately we have relatively little data on trans men who have become pregnant and given birth since the number is so small, but there have been some small studies and surveys that indicate prior testosterone use did not affect their chances of becoming pregnant or completing the pregnancy (compared to non-trans women).  This is a good start but there’s much more research needed to include more segments of the population and the long term safety of hormone replacement and its effects on transgender fertility.  

Whether you want to avoid pregnancy or are trying to conceive, it’s important to talk to your healthcare provider about your fertility options.  Testosterone can cause birth defects which is why it’s important to be monitored and speak with your healthcare provider about your fertility options.   

Managing Fertility: Low Testosterone and Assisted Reproductive Technologies

As we know, testosterone is essential for many body functions and processes including fertility.  Testosterone therapy has grown in popularity as a way to improve IVF outcomes, especially in those with poor ovarian reserve.  Researchers are still unclear as to exactly how testosterone can lead to fertility problems in women and much more research is needed in the area.   

There are both clinical interventions as well as natural ways to encourage testosterone production.  Clinical interventions include hormone therapy to supplement low testosterone levels as well as DHEA supplementation.  DHEA (dehydroepiandrosterone) is a precursor hormone that your body can convert to testosterone, although its role isn’t completely understood and more research is needed in the area.

Natural ways to encourage testosterone production include lifestyle changes that can have a positive impact on your fertility.  For most people that means maintaining a healthy weight, eating a healthy diet, getting enough sleep, and keeping your stress levels under control.  Excessive stress can cause cortisol (the stress hormone) levels to rise which has been linked to low testosterone as well.  

Conclusion: The Future of Testosterone Research and Female Fertility

We are still discovering the role of testosterone in female fertility and there is still much to learn on the effects of hormone therapy on fertility.  Once considered a fertility killer, testosterone actually plays a role in follicle development and release.  We know that the effect of hormone therapy on fertility is potentially reversible, but other factors are less clear.  New research suggests there’s more to androgens than previously thought when it comes to female fertility and has opened new avenues to the future of testosterone research.  Further research is needed to understand the complete role of testosterone and androgens in female fertility and to provide better evidence-based information to healthcare providers and patients alike.         

FAQs 

Is testosterone therapy recommended for fertility issues in women?

Currently, the safety of testosterone therapy in women is under research and being established.  Some studies have found testosterone to have a significant impact on the fertility rate of certain women in IVF cycles, but much more research is needed in this area.  Even though testosterone therapy is common, a global consensus position statement on the use of testosterone therapy in women states “there are no clearly established indications for testosterone therapy for women.” 

How does testosterone therapy affect fertility in transgender individuals?

Testosterone is a dose-dependent ovulation suppressant.  As long as you are taking your dose as prescribed, it will work to suppress ovulation in a transgender individual.  No harm has been shown to egg quality or reserve and once testosterone therapy is stopped, ovulation should return.  It’s important to note that testosterone is not a form of birth control and you can still get pregnant while taking testosterone.  Testosterone can harm a developing fetus and is not recommended during pregnancy.    

Can women with high testosterone levels have fertility issues?

High levels of testosterone in women can be associated with symptoms including irregular or absent periods, excess facial and body hair growth, blood sugar imbalances, thinning hair on the scalp, and excessive acne.  Women with high testosterone levels may also have fertility issues such as difficulty getting pregnant.  

Are there any risks associated with testosterone therapy in women?

Although there are risks associated with any supplementation, those associated with testosterone therapy in women remain uncertain.  It is often prescribed for declining sexual function in postmenopausal women, but there are no international guidelines for the use of testosterone in women.  This practice guideline from the Endocrine Society addresses the use of androgens in women and offers recommendations for therapeutic interventions.