What Happens When You Stop TRT? Testosterone Cessation Explained

Why TRT Suppresses Your Own Testosterone Production

When you take exogenous testosterone, your hypothalamus detects elevated circulating levels and reduces its output of GnRH. This suppresses pituitary LH and FSH secretion. Without LH signalling, the Leydig cells in your testes stop producing testosterone. This is called HPG axis suppression — and it happens to some degree in virtually every man on TRT.

The Timeline After Stopping TRT

Weeks 1–4: Testosterone Levels Fall

After the last dose, serum testosterone levels decline at a rate determined by the formulation's half-life:

• Reandron (testosterone undecanoate): Half-life ~21 days; levels decline over 4–6 weeks
• Testosterone enanthate: Half-life ~4–7 days; levels decline over 2–3 weeks
• Testosterone gel: Half-life ~12–24 hours; levels decline within days of last application

During this period, deficiency symptoms typically return.

Weeks 4–16: HPG Axis Recovery

LH and FSH begin to rise as the negative feedback from exogenous testosterone is removed. In men with functional secondary hypogonadism, the axis typically recovers within 4–16 weeks. In men with primary hypogonadism (testicular failure), endogenous testosterone production will not recover meaningfully.

Months 3–6: Sperm Recovery (Variable)

A 2014 systematic review in the Asian Journal of Andrology found that most men recover sperm production after stopping testosterone, with a median recovery time of approximately 3–6 months. However: recovery is not guaranteed, and 5–10% of men do not recover to pre-TRT sperm concentrations.

HCG and/or SERMs such as clomiphene can accelerate HPG axis recovery after TRT cessation in men with secondary hypogonadism.

Can TRT Ever Be Stopped Permanently?

Primary Hypogonadism (Permanent)

Men with primary testicular failure — Klinefelter syndrome, bilateral orchitis, post-chemotherapy — have structural damage that cannot recover. For these men, TRT is almost always lifelong.

Secondary Hypogonadism (Potentially Reversible)

Men with secondary hypogonadism caused by reversible factors may be able to discontinue TRT after addressing the underlying cause:

• Obesity-related: Significant weight loss may restore HPG axis function
• Sleep apnoea-related: Effective CPAP treatment can meaningfully improve testosterone
• Medication-induced: If testosterone-suppressing medications are discontinued, HPG recovery may occur
• Anabolic steroid history: Men may recover HPG function with time and/or HCG/clomiphene support

Stopping TRT to Try for a Baby

The approach:

1. Stop TRT and allow exogenous testosterone to clear
2. Commence HCG (typically 1500–3000 IU subcutaneously 3× per week) to stimulate intratesticular testosterone and restart spermatogenesis
3. Add clomiphene or FSH if sperm recovery is incomplete after 3–6 months of HCG alone
4. Monitor semen analysis every 8–12 weeks until sperm count is adequate

References

1. Ramasamy R, et al. Recovery of spermatogenesis following testosterone replacement therapy or anabolic-androgenic steroid use. Asian J Androl. 2014.
2. Endocrine Society of Australia — MJA position statement.
3. Bhasin S, et al. Testosterone Therapy in Men with Hypogonadism: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2018.
4. Cleveland Clinic — Testosterone Replacement Therapy.
5. Hormones Australia — Hypogonadism.