Clinically reviewed by Haley Collins, NP
If you have a penis and sex has changed lately, it can be easy to wonder whether low testosterone is the reason.
Maybe you’re less interested in initiating. Maybe you want sex but your erections aren’t as reliable. Maybe you can get hard but not stay hard. Maybe orgasm takes forever—or doesn’t happen at all. Maybe you’re still having great sex, but your body is responding differently than it used to.
These are all different things. And testosterone doesn’t affect all of them in the same way.
For gay, bi, queer, and other men who have sex with men, or for anyone with a penis, that distinction can be especially important. Testosterone can affect sexual desire, erections, and other aspects of sexual function—but not always in the ways people assume.
A lot of conventional information about “male sexual function” still assumes one particular kind of sex: erection, penetration, ejaculation, done. That’s not a particularly good description of many people’s sex lives—and it can make it harder to figure out what’s actually going on when something changes.
Here’s what testosterone can affect, what it may not fix, and how to think about low T without turning every change in your sex life into a hormone problem.
First: libido, erections, ejaculation and orgasm are not the same thing
They often overlap, but your body runs them through different pathways.
Libido is your interest in or desire for sex.
Arousal is your physical and psychological response to sexual stimulation.
Erection is a vascular and neurological process: blood has to flow into the penis and remain there.
Orgasm is the pleasurable neurological and muscular response we associate with climax.
Ejaculation is the release of semen. It usually happens around the same time as orgasm, but the two are not identical. You can orgasm without ejaculating, and changes in ejaculation do not necessarily mean your ability to orgasm has changed.
That matters because testosterone has a relatively strong relationship with some parts of sexual function—especially desire—and a much less direct relationship with others.
What low testosterone can do to your sex drive
This is probably the clearest connection.
Low libido is one of the more characteristic symptoms of testosterone deficiency. In people who have both symptoms and consistently low testosterone levels, treatment with prescription testosterone can increase sexual desire and sexual activity. Large randomized studies of older men with low testosterone have found improvements in sexual interest after testosterone treatment. It is important to note that if testosterone levels are not low, more testosterone is not necessarily better and could lead to adverse effects.
That doesn’t necessarily mean going from “not horny” to “constantly horny.” You might notice more sexual thoughts, more interest in initiating, more responsiveness when a partner initiates, or simply that sex feels worth pursuing again.
There’s also no single correct amount of sexual desire. If your libido has always been low and you’re perfectly happy with it, that isn’t automatically a problem that needs treatment. However, if you are also having other symptoms that impact your well being that are consistent with low testosterone, it may be worth looking into.
The more relevant question is: Has something changed, and does that change bother you?
And even then, testosterone is only one possibility. Stress, depression, relationship dynamics, poor sleep, alcohol and other substances, chronic illness, pain, and medications—including some antidepressants—can all affect desire. The Endocrine Society specifically cautions that symptoms such as reduced libido, energy, and mood have many possible causes and aren’t enough on their own to diagnose low testosterone.
Can low T cause erection problems?
It can contribute. But testosterone is not an on/off switch for erections.
Some people with low T notice fewer spontaneous or morning erections, difficulty getting fully hard, or erections that feel less reliable. Testosterone treatment can modestly improve erectile function in people who genuinely have testosterone deficiency.
But erections depend heavily on blood flow, nerve function, medications, psychological state, and cardiovascular health. That’s why you can be extremely turned on and still not get the erection you want—and why you can get an erection when you aren’t particularly interested in sex.
It’s also why testosterone usually isn’t considered a stand-alone treatment for erectile dysfunction. The American Urological Association notes that in people with both ED and testosterone deficiency, normalizing testosterone may improve response to medications such as sildenafil or tadalafil, but testosterone alone often isn’t enough to treat ED.
So if your libido is great but you suddenly can’t stay hard while topping, “I must have low T” probably shouldn’t be the end of the investigation.
Depending on the person, possibilities could include medication effects, vascular health, anxiety, pelvic-floor issues, alcohol or substance use, changes in sensation, or simply the very normal fact that erections become somewhat less automatic with age. Erectile dysfunction does not mean you are broken, less than, or no longer interested in your partner. It is merely a physiologic change that can be treated.
What if you mostly bottom?
Low testosterone isn’t only relevant if you need an erection for penetration.
If you’re primarily receptive during anal sex, changes in libido can still make a big difference in how interested or engaged you feel during sex. Testosterone may also affect general energy and sexual motivation.
But testosterone is not required for anal pleasure.
The nerves, pelvic floor, prostate and other structures involved in receptive pleasure don’t suddenly stop working because your testosterone level is lower. You also do not need to be erect to be aroused, enjoy penetration or have an orgasm.
That can be an important distinction if your body has changed with age. Losing some erectile reliability doesn’t have to mean losing access to satisfying sex.
And if receptive sex itself has become painful, uncomfortable or less pleasurable, low T may not be the most useful place to start. Pelvic-floor tension, hemorrhoids or fissures, prostate issues, GI conditions, general aging (which causes rectal tissue changes,) changes in sexual technique, anxiety and other causes may deserve attention instead.
What about orgasm?
This is where the testosterone story gets considerably murkier.
People with low testosterone sometimes report reduced orgasm intensity, delayed orgasm or difficulty reaching orgasm. But testosterone treatment has not consistently been shown to fix orgasm or ejaculation problems.
In one randomized trial of men with both low testosterone and ejaculatory difficulties, testosterone treatment did not significantly improve ejaculatory function compared with placebo. Other trials have found some improvement, so the overall evidence is mixed.
That means a new inability to come shouldn’t automatically be chalked up to low T.
Delayed orgasm and anorgasmia can be associated with medications—SSRIs are a particularly common example—as well as nerve changes, pelvic-floor issues, diabetes, alcohol or drugs, psychological factors, certain prostate treatments and other medical conditions.
And remember: orgasm and ejaculation are separate.
You may have a satisfying orgasm with little or no semen. Or you may notice less force or volume when you ejaculate even though orgasm still feels good.
Does testosterone make sex “better”?
Not necessarily.
If you actually have testosterone deficiency, restoring your testosterone to a typical physiological range may improve symptoms caused by that deficiency—particularly low desire.
That is very different from saying that more testosterone equals better sex.
If your testosterone is already normal, adding testosterone isn’t an evidence-based treatment for a mediocre sex life, erection problems or difficulty orgasming. And increasing your testosterone beyond normal ranges is not the goal of testosterone replacement therapy.
Sex is also relational, neurological, vascular, psychological, physical and contextual. Testosterone can affect part of the system. It is not the system.
How do you actually know if you have low T?
You can’t diagnose it based on how horny you feel.
Current guidelines recommend diagnosing testosterone deficiency when both of these are present:
- symptoms that could be related to low testosterone, and
- repeatedly low testosterone levels on appropriately performed blood tests.
Because testosterone naturally fluctuates over the course of the day, clinicians generally confirm a low result with at least two early-morning testosterone measurements. A total testosterone level around 300 ng/dL is commonly used as part of the clinical evaluation, although the number has to be interpreted alongside symptoms, lab methods and sometimes free testosterone levels.
The point isn’t to chase a particular number. It’s to figure out whether testosterone deficiency actually explains what you’re experiencing.
Other reasons sex may change in midlife
Testosterone gets a lot of attention because it feels like a satisfyingly simple explanation. But sexual changes in your 40s, 50s and beyond can have multiple overlapping causes.
Things worth considering include:
- cardiovascular health and blood pressure
- diabetes or insulin resistance
- sleep apnea and poor sleep
- depression, anxiety or chronic stress
- relationship changes
- antidepressants and other medications
- alcohol and recreational substances
- chronic pain or illness
- pelvic-floor dysfunction
- prostate or urinary symptoms
- HIV and other chronic health conditions
- changes in the kind of stimulation your body responds to
Sometimes the answer is low T. Sometimes it’s tadalafil. Sometimes it’s changing an antidepressant. Sometimes it’s treating sleep apnea. Sometimes it’s adding a toy, changing positions, using more stimulation or redefining what counts as sex rather than trying to make your body behave exactly as it did at 25.
Often, it’s a combination of things.
One more thing: testosterone can affect fertility
If there’s any possibility that you want to use your sperm to have biological children, tell your clinician before starting testosterone.
Taking testosterone from outside the body can suppress the hormonal signals your testes need to produce sperm. In some people, sperm production drops dramatically or stops altogether while taking testosterone.
That doesn’t mean someone who wants to preserve fertility can never address low testosterone. It does mean the treatment plan may be different. There are multiple treatments to help improve your testosterone that preserve fertility. These treatments focus more on helping your body produce its own testosterone.
So: what can testosterone actually change?
A useful shorthand is:
Desire: Quite possibly. Low libido is one of the sexual symptoms most closely associated with testosterone deficiency.
Erections: Maybe. Low T can contribute to erection difficulties, but erections depend on much more than testosterone. ED often needs its own evaluation and treatment.
Orgasm: Possibly, but the evidence is much less clear. Difficulty orgasming has many other common causes.
Ejaculation: Testosterone isn’t a reliable fix for delayed ejaculation, low volume or other ejaculatory changes.
Anal pleasure: Not directly dependent on having high testosterone—or on having an erection.
Your overall sex life: Testosterone is one variable among many.
If something about sex has changed, you don’t have to settle for either “you’re getting older” or “take testosterone.” A good evaluation should get more specific: What changed? Desire? Erections? Sensation? Orgasm? Ejaculation? Comfort? And what do you actually want to be different?
Those answers are much more useful than treating “sexual function” like it’s one thing.
