Testosterone suppresses sperm production and can cause azoospermia. AUA/ASRM (2021): for a man interested in current or future fertility, testosterone monotherapy should not be prescribed. Recovery after stopping takes many months and is not always complete.
Testosterone therapy and male fertility
If you are trying to conceive, or may want children in future, this is the single most important thing to know about testosterone replacement therapy: it suppresses sperm production, and can stop it altogether.
Why this happens
Testosterone taken from outside the body signals to the brain that levels are adequate. The pituitary gland responds by reducing the hormones that drive the testes — FSH and LH. Without those signals, sperm production falls and may cease entirely, resulting in azoospermia, meaning no sperm in the ejaculate.
This is a predictable consequence of the treatment, not a rare side effect.
What the guideline says
The AUA/ASRM guideline on male infertility states plainly: for the male interested in current or future fertility, testosterone monotherapy should not be prescribed. It also advises that clinicians should inform patients of the deleterious effect of testosterone therapy on sperm production, and that men should be counselled that testosterone monotherapy is not a treatment for male infertility.
Recovery is possible but not guaranteed
Sperm production often returns after stopping testosterone. It can take many months — spermatogenesis alone takes around 72 to 90 days, and hormonal recovery takes longer. Recovery is not always complete, and duration of use appears to matter.
If you have low testosterone and want children
Alternatives exist that raise testosterone without suppressing sperm production. The guideline notes that aromatase inhibitors, hCG and selective oestrogen receptor modulators may be used, and that clomiphene and tamoxifen are not FDA-approved for use in men, so this is off-label prescribing requiring proper counselling.
The key point is that this is a specialist decision. See a urologist, andrologist or reproductive endocrinologist rather than a general testosterone clinic.
Where testosterone comes from unexpectedly
Gym supplements are a recognised hidden source of anabolic steroids, sometimes without the buyer knowing. If you are being investigated for infertility, disclose everything you take — including anything bought informally or online.
What to do
If you are on testosterone and want to conceive, do not stop abruptly on your own. Speak to a specialist about a managed plan. If testosterone has been suggested to you and you may want children, say so before starting — this changes the recommendation entirely.
Sources
- AUA/ASRM — Diagnosis and treatment of infertility in men (2021)
Frequently Asked Questions
Does testosterone replacement cause infertility?▾
Yes — in most men. All forms of TRT (injections, gels, patches, pellets) suppress the pituitary signals driving sperm production. Most men become severely oligospermic or azoospermic within 2–3 months of starting TRT. The same applies to anabolic steroids. Men planning to conceive should not start TRT — use fertility-preserving alternatives (clomiphene, hCG) that raise testosterone without suppressing sperm production.
How long after stopping testosterone will sperm return?▾
In 50% of men, sperm parameters recover toward baseline within 6 months of stopping TRT. 90% recover within 24 months. Recovery can be accelerated with FSH/hCG injections or clomiphene under medical supervision. Men who used TRT for shorter periods generally recover faster. A reproductive urologist should supervise the discontinuation and recovery process.
Can I take testosterone and father children at the same time?▾
Standard TRT makes most men unable to father children naturally during treatment. Some men maintain residual sperm — always confirm with a semen analysis. If you must continue testosterone for medical reasons and want to conceive, concurrent hCG injections can partially maintain spermatogenesis in some men. This is a specialised management scenario requiring a reproductive urologist.