Testosterone therapy and fertility: what every man should know first

Why testosterone therapy suppresses sperm

Sperm production depends on a high concentration of testosterone inside the testes, which is driven by LH and FSH from the pituitary gland. When you take testosterone, your brain senses plenty of it in the bloodstream and turns those signals down. Blood testosterone rises, but testosterone inside the testes falls, and sperm production slows or stops. The testes may also shrink somewhat.

This happens with gels, injections, pellets and oral products alike, because the effect comes from the hormone itself rather than the delivery method. How deep the suppression goes varies between men, but it is common enough that guidelines treat near-term fertility plans as a reason not to start.

Testosterone therapy is not birth control

Even though sperm counts often drop, they do not fall to zero in every man, and pregnancies have occurred during treatment. If you do not want a pregnancy, keep using a reliable contraceptive method.

If you are already on testosterone and now want to start a family, do not simply stop on your own. Talk with your clinician about a plan, which may include a referral to a urologist or fertility specialist, a baseline semen analysis and a structured approach to restarting your own production.

If you might want children later

Ask for a semen analysis before starting. It gives you a baseline, and if you later have trouble conceiving, it helps separate the effect of the medication from a problem that was already there. Some men also consider banking sperm before starting long-term therapy.

The AUA notes that men who want to preserve fertility can be offered alternatives, including selective estrogen receptor modulators such as enclomiphene or clomiphene, hCG and aromatase inhibitors. These raise your own testosterone or protect sperm production rather than replacing the hormone. Their use for this purpose is off-label.

How enclomiphene differs

Enclomiphene blocks estrogen's feedback in the brain, so the pituitary releases more LH and FSH. The testes respond by making more testosterone and, in many men, maintaining sperm production. It only works when the testes can respond; if the problem is in the testes themselves, LH is already high and stimulating it further adds little.

Enclomiphene prescribed through HealifyMD is a compounded preparation from $129 per month, so it is not FDA-approved and has not been FDA-reviewed for safety or effectiveness. Related drugs in the same class have been linked to mood changes and visual symptoms such as blurring or flashes; stop and contact your clinician promptly if your vision changes.

Recovering fertility after stopping

After testosterone therapy stops, the brain usually resumes LH and FSH release and sperm production gradually returns, but the timeline is measured in months, and sometimes longer. Recovery tends to be slower after longer use, higher doses and at older ages, and in a minority of men it is incomplete. A fertility specialist may use hCG or other medications to support recovery, and repeat semen analyses track progress.

Getting an accurate semen analysis

MedlinePlus advises abstaining from ejaculation for about 2 to 7 days before collecting a sample; your lab will give specific instructions. Because sperm counts vary from day to day, an abnormal result is usually repeated, and two or more samples may be needed. One poor result does not mean you are infertile.

HealifyMD's Male Fertility Test is $299 one-time. Your clinician can explain what the results mean for you and whether a referral to a urologist or fertility specialist makes sense.

Age and sperm quality

Men can father children later in life than women, but sperm quality and the time to conception tend to decline with age. Habits that support sperm health include not smoking, limiting alcohol, maintaining a healthy weight, staying active, avoiding anabolic steroids and limiting prolonged heat exposure to the groin, such as frequent hot tubs. Because sperm take roughly two to three months to develop, changes take time to show up in test results.