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Does a Vasectomy Decrease Testosterone?

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Having a vasectomy is a big decision in a man’s life and one that should not be taken lightly. Once you’ve made up your mind that you never want to have any more children, there’s no more reliable form of contraception.

It’s a life altering procedure, but does a vasectomy also alter testosterone production? Does having a the procedure mean you should worry about the effects on your muscle mass and strength that you’ve worked so hard for?

In this article we bring you the low down on vasectomies and their effect on testosterone.

In this article you will learn:

  • What is a vasectomy?
  • Will it affect your T levels?
  • Are there any side effects?
  • Summary

What is a vasectomy?

The procedure is a minor operation that involves the clamping or cutting of the vas deferens – narrow but muscular tubes that adjoin the testicles to the urethra.

As the sperm flows out of the testicles, through the vas deferens, and into the urethra during ejaculation, a vasectomy prevents any sperm from travelling to, and mixing with semen – whilst sperm are still produced, they cannot mix with semen and ejaculate – this prevents the egg from being fertilized and pregnancy occurring.

The procedure is considered a permanent method of birth control unless the operation is reversed (although this is not always a successful procedure), however it can take a few months for all of the sperm to be completely removed from the semen and absorbed, so alternative birth control is usually used until testing shows a zero sperm count.

It is estimated that about 500,000 in the US have the operation each year [1] at an average age of 31 years [2].

So if sperm is removed from the semen can it affect your T levels? Let’s take a look at what the research says…


Key Point: A vasectomy is a minor operation where the tubes that supplies semen with sperm are either cut or clamped. Read on to find out how it effects testosterone.

Will it affect my testosterone levels?

Here’s a run down of the research. As you can see it provides an interesting perspective:

#Study 1: Goebelsmann et al [3]

In this early study, 41 men had their sex hormones – including testosterone, measured 3 times over a 24 month period. Each of the men had undergone a bilateral vasectomy. Results measures showed that there was no significant difference in any of the sex hormones, and no change in T levels over the 24 month period.

They concluded that the validity of studies which report significant hormonal changes after the procedure needs to be questioned. 

Interestingly there are even studies that show vasectomies could slightly increase your T levels!

#Study 2: Honda et al [4]

In this study by Honda et al, men aged below 60 years were recruited in order to investigate whether the association with the operation might have a hormonal basis. 

Levels of T were measured in 33 of the vasectomized men against levels in 33 non-vasectomized controls of the same age, weight and height. The results were not as expected, with the vasectomy group demonstrating higher T-levels than the control group. 

#Study 3: Reinberg et al [5]

Similar to the study by Honda, this research paper, published in the journal Fertility and sterility, recruited 260 men to assess changes in a number of hormones pre and post-vasectomy.

The results showed that compared with the pre-op group, T levels were slightly, yet statistically significantly elevated.

#Study 4: Smith et al [6]

In another study showing increased T levels, post-op plasma hormone levels were compared with pre-vasectomy in a group of 56 men. Testosterone was measured at 6 months after the operation, and again at 2 years.

At 6 months after the vasectomy, plasma testosterone levels demonstrated a statistically significant elevation, mean plasma estradiol levels – a type of estrogen,  were lower. Levels remained the same at the 2 year point also.


Key Point: Research shows that Testosterone levels do not decrease and in some cases may even slightly increase after a vasectomy.

Are there any side effects to a vasectomy?

So research suggests that there are no negative effects of the operation when it comes to T levels. The fact that a couple of studies show slight increases is good, but of course doesn’t mean you should book in tomorrow just to boost your hormone levels.

But are there any side effects you need to be aware of?

Here’s a look at what you need to know if you’re planning the operation:

As most operations are conducted on men aged in their thirties and forties, there is potential for long-term side effects and consequences.

Sexual function

As the nerves remain untouched during the operation, a vasectomy does not lead to impotence or other sexual difficulties. Research suggests that there may even be a positive effect on sexual activity, as the risk of pregnancy is reduced therefore there’s less to worry about when you are ‘caught in the moment’.

Various studies have shown no effect on impotence or sexual difficulties and vasectomies can even cause a positive impact on sexual function, especially on desire and sexual satisfaction, in the majority of men undergoing surgery [7]. The amount of semen ejaculated does not change meaning you’ll not even notice the difference.

Prostate cancer

This type of cancer is the second most common in men Worldwide [8]. The research has been somewhat conflicting between vasectomy and prostate cancer and a convincing biological mechanism for a causal relationship has yet to be discovered.

Recently, the American Urological Association (AUA) performed a meta-analysis of a number of comparative studies and found no statistically significant difference in relative risk of prostate cancer in vasectomized men compared to men without the operation [9].

Summary – Does a vasectomy reduce testosterone?

A vasectomy is a minor operation where the tubes that supply your semen with sperm are either cut or clamped in order to eliminate sperm from your ejaculation.

Studies show that the operation does not reduce testosterone, and in some cases slightly increase it. However this is not cause for planning an operation purely based on potential benefits.

To date there has been conflicting research based on potential side effects, however most published reports suggest limited to no consequences.


  1. Pile, JM et al. Demographics of vasectomy – USA and international. Urologic Clinics of North America. 2009; 36(3): 295–305
  2. Coward, RM et al.  Vasectomy Reversal Outcomes in Men Previously on Testosterone Supplementation Therapy. Urology. 2014; 84: 1335-1341
  3. Goebelsmann, U et al. Serum gonadotropin, testosterone, estradiol and estrone levels prior to and following bilateral vasectomy. In: Lepow IH, Crozier R eds. Vasectomy: immunologic and pathophysiologic effects in animals and man. (Proceedings of a workshop, Airlie, Virginia, April 24-27, 1978). New York, Academic Press, 1979. 165-81.
  4. Honda, GD et al. Vasectomy, cigarette smoking, and age at first sexual intercourse as risk factors for prostate cancer in middle-aged men. Br J Cancer. 1988; 57(3): 326–331
  5. Reinberg, A et al. Annual variation in semen characteristics and plasma hormone levels in men undergoing vasectomy. Fertil Steril. 1988;49(2): 309-15.
  6. Smith, KD. An investigation of plasma hormone levels before and after vasectomy. Fertil Steril. 1976; 27(2): 144-51.
  7. Bertero, E et al. Assessment of sexual function in patients undergoing vasectomy using the international index of erectile function. Int Braz J Urol. 2005; 31(5)
  8. Ferlay J, Shin HR, Bray F, et al. GLOBOCAN 2008, Cancer incidence and mortality worldwide: IARC CancerBase No. 10. Lyon, France: International Agency for Research on Cancer; 2010.
  9. Sharlip ID, Belker AM, Honig S, Labrecque M, Marmar JL, Ross LS, Sandlow JI, Sokal DC; American Urological Association. Vasectomy: AUA guideline.J Urol. 2012;188(6 Suppl): 2482-91