By Mike Kocsis | 7 minutes read | Last updated: December 19, 2024
Medically Reviewed by Dr. George Touliatos
With its promise to improve vitality, libido, and well-being, testosterone replacement therapy (TRT) has become a popular and sought-after solution for men with low testosterone (low T).
However, amidst this increasing popularity, concerns have been raised regarding the potential impact of TRT on male fertility. As more men choose TRT to deal with low T symptoms, understanding the connection between TRT and fertility has now become more important than ever.
This article sheds light on the relationship between male fertility and TRT, providing evidence-based insights and addressing misconceptions.
Role of testosterone in fertility
In men with healthy testosterone levels, one millilitre (mL) of semen typically contains 15 to 200 million sperm. If your testosterone levels are low, you may have fewer than 15 million sperm per millilitre, which is considered a low sperm count. In addition to testosterone, luteinising hormone (LH) and follicle-stimulating hormone (FSH) are also involved in sperm production. The interplay between these hormones is essential for normal sperm production.
Let’s see how these hormones work together in a coordinated manner to form sperm;
Luteinising hormone (LH): The hypothalamus releases gonadotropin-releasing hormone (GnRH) to stimulate the production of LH and FSH by the pituitary gland. LH stimulates Leydig cells present in the testes to produce and release testosterone. Adequate levels of LH are required for normal testosterone production.
Follicle-stimulating hormone (FSH): It stimulates Sertoli cells within the testes to release certain factors sperms need for proper nourishment, development and maturation.
Testosterone: It initiates and maintains sperm production. It promotes the maturation and division of germ cells that eventually turn into mature sperm cells.
Testosterone is also involved in the development of secondary sexual characteristics in men. Additionally, it contributes to the regulation of libido (sex drive) and sexual performance. It also supports the health of testicular tissues and structures required for healthy sperm production.
The connection between TRT and men’s fertility
Since TRT increases testosterone levels in the blood, it is often believed it can increase fertility as well. But in reality, the opposite is true. The truth is, TRT reduces sperm count and negatively impacts fertility.
This treatment involves the administration of exogenous (external) testosterone, which increases testosterone levels in the blood but not in the testes, where it is required for sperm production. So even if you have normal testosterone levels in your blood but low testosterone levels in the testes, you will still have a low sperm count.
TRT can further reduce your sperm count by diminishing the production of endogenous (internal) testosterone. Serum testosterone creates a feedback loop that controls the production of LH, FSH, and GnRH from the brain. A normal serum testosterone level promotes negative feedback. It sends signals to the brain, telling it that the body has enough testosterone, so there is no need to produce LH, FSH, or GnRH anymore. Resultantly, the production of LH, FSH, and GnRH diminishes.
As testes do not receive any signal in the form of LH to produce testosterone, testicular testosterone levels decline. Data shows men undergoing TRT have LH and FSH levels less than one-half of their original levels. This way, TRT impairs sperm production and fertility. Due to its ability to negatively influence fertility, exogenous testosterone is often considered a male contraceptive.
If you plan to start TRT and have children in the near future, you should discuss your plans with your doctor. They will help you find a suitable solution to maintain fertility and expand your family.
How to maintain fertility on TRT?
Here is what you need to do to maintain your fertility while undergoing TRT.
Consult with a knowledgeable healthcare professional:
Low T does not really make a man infertile. In fact, most men with low serum testosterone can still have babies because they produce enough testicular testosterone and sperm.
Hence, if you plan to have TRT and expand your family, ask your doctor whether it is the right time to start the treatment or if you should first try to get pregnant. If you still want to start TRT, discuss methods you can use to maintain your fertility. A knowledgeable doctor can provide personalised advice and design a bespoke plan based on your specific needs.
Consider hCG supplementation:
Human chorionic gonadotropin (hCG), also known as pregnancy hormone, is released by trophoblast cells throughout pregnancy in women. It shows structural similarity to LH and binds to the same receptor in humans as LH. Because of this reason, it can mimic the functions of LH.
hCG has been approved by the FDA for the treatment of male infertility and other medical conditions. Like LH, it can stimulate testosterone and sperm formation in men.
Consider sperm preservation:
Another method to protect your fertility is to preserve healthy sperm by freezing them. It is a simple process during which your semen sample is analysed, and healthy sperm are put in liquid nitrogen storage tanks. Frozen sperm can then be used for in vitro fertilisation (IVF), in which sperm and egg are fertilised outside the body. Later, the embryo is implanted in the womb. Preserved sperm stays healthy for years or even decades.
Get your hormone levels checked regularly:
Regular monitoring of important hormones like testosterone, FSH, and LH will help you maintain hormonal balance and adjust your hormones when needed. You can get your hormone levels checked with a simple blood test that can even be done in the comfort of your own home!
How can men use hCG to maintain fertility on TRT?
hCG is given by injection, and its half-life is approximately 2 days. Protocol for hCG injections differs from patient to patient based on individual needs, but generally, 2 to 3 injections are given weekly. Doctors usually start with low hCG doses like 125, 250, and 500 IU. They can increase your dose based on your body’s response.
You can inject hCG injections either subcutaneously or intramuscularly. The best subcutaneous sites for these injections are:
- Upper outer arm
- Upper outer buttock
The best intramuscular sites for hCG injections are:
- Front of thighs
- Lower abdomen
- Side of upper arms
Benefits of using hCG with TRT
- HCG can significantly increase intratesticular testosterone levels in men undergoing TRT. Studies show that men who received testosterone noticed a 94% reduction in their intratesticular testosterone levels. But when they used testosterone in combination with 250 IU hCG, intratesticular testosterone dropped by only 7%. Increasing the hCG dose to 500 IU increased their intratesticular testosterone levels by 26%.
- Data reveals TRT can cause azoospermia (complete absence of sperms in ejaculations) within 10 weeks of starting the therapy. When hCG is used in combination with testosterone, it can significantly reduce TRT-induced azoospermia.
- TRT can reduce the production of GnRH by the hypothalamus, leading to testicular atrophy (shrinkage). You can reverse this effect by using hCG, which increases endogenous testosterone levels and resists testicular shrinkage.
- Additionally, hCG can help men with low testosterone improve their sex drive, cognitive functions, and exercise capacity.
FAQs
Women often ask: My husband takes testosterone injections. Can I still get pregnant?
Testosterone injections can reduce sperm count in men. If you want to conceive, you should consider hCG with TRT to prevent TRT-induced infertility or restore your sperm count. Discuss your plans of having children with your doctor before starting TRT to find out what fertility options you have and what you can do about them.
Should you try TRT and hCG?
TRT is an FDA-approved procedure used to treat testosterone deficiency in men. It is very effective in managing low T symptoms and improving overall health. However, despite all these benefits, it has the potential to make men infertile.
If you are starting TRT and are concerned about your fertility, you should consider having hCG injections as they can maintain your fertility and reverse other TRT side effects.
Is TRT infertility irreversible?
TRT-induced infertility is mostly temporary. You can reverse it by stopping testosterone administration. Your intratesticular testosterone levels will start rising again, which can take anywhere from months to years, depending on the duration of your treatment and the amount of testosterone you used during it.
How much does hCG increase testosterone?
Data reveals that men having hCG monotherapy can experience a 49.9% increase in testosterone levels, while men having it with testosterone can expect their testosterone levels to rise up to 26%. Results can vary depending on your hCG dosage.
How long does hCG take to work in males?
It depends on various factors, including your hCG dose, testosterone dose, and health condition when you start taking hCG. You can expect the treatment to show its results within 3 to 6 months of starting it.
How much hCG to take with TRT?
Each patient has different hCG needs depending on his specific health condition and health-related goals. Hence, your doctor will formulate a customised hormone therapy (HT) for you according to your individual needs.
References/Bibliography/Citations/Scientific studies/Further reading
Tsametis, C.P. and Isidori, A.M., 2018. Testosterone replacement therapy: For whom, when and how?. Metabolism, 86, pp.69-78.
Lee, J.A. and Ramasamy, R., 2018. Indications for the use of human chorionic gonadotropic hormone for the management of infertility in hypogonadal men. Translational andrology and urology, 7(Suppl 3), p.S348.
El Meliegy, A., Motawi, A. and Abd El Salam, M.A., 2018. Systematic review of hormone replacement therapy in the infertile man. Arab journal of urology, 16(1), pp.140-147.
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