There are several medical references showing testicular fibrosis after vasectomy. This important complication it is not featured in the vasectomy consent process and has implications for testicular function and early andropause in vasectomized men.
Vasectomy is frequently described as a simple, convenient, inexpensive, permanent surgical birth control method for men. Approximately 500,000 vasectomies are performed in the United States each year. Another 40,000 are performed in the United Kingdom, with thousands more performed worldwide. Vasectomy is widely accepted as a safe procedure with acceptable short-term side effects (primarily bleeding or infection) and few long-term side effects. Chronic post-vasectomy scrotal or testicular pain is well described in the medical literature, but is not prominently featured on vasectomy consent forms. Testicular damage due to vasectomy has been a concern, but this information has not made its way into the pre-vasectomy consent process.
Testicular damage is well documented in all mammalian vasectomy models studied to date, including rodents (rabbits, rats, mice, hamsters, and guinea pigs), canines, non-human primates, and other mammals (sheep, horses, and others). There are studies in humans showing testicular damage (testicular fibrosis) after vasectomy that date back to 1985 like this reference from The New England Journal of Medicine.
"To determine whether there are any deleterious changes in the human testis after vasectomy, we obtained testicular biopsy specimens from 31 healthy men undergoing vasectomy reversal and from 21 healthy, fertile volunteers. Morphometric analyses of these specimens revealed a 100 per cent increase in the thickness of the seminiferous tubular walls (P less than 0.001), a 50 per cent increase in the mean cross-sectional tubular area (P less than 0.001), and a significant reduction in the mean number of Sertoli cells (P less than 0.01) and spermatids (P less than 0.01) per tubular cross section in the post-vasectomy group, as compared with the control group. Focal interstitial fibrosis was observed in 23 per cent of the specimens from the post-vasectomy group and in none from the control group.We conclude that significant morphologic changes occur in the human testis after vasectomy. The presence of focal interstitial fibrosis was associated with a high incidence of infertility in this series. There was a significant correlation (P less than 0.01) between interstitial fibrosis and infertility in patients who underwent a surgically successful vasectomy reversal (sperm in the ejaculate). None of the other measured characteristics correlated with infertility after vasectomy reversal."
Focal interstitial fibrosis is essentially scar tissue. The pressure-induced effects of closing off the sperm delivery system could cause this scarring by interrupting the flow of sperm through the vas deferens (the "tubes" that are cut during vasectomy). An alternate hypothesis supported by animal studies suggest that the fibrosis is caused by inflammation due to an auto-immune reaction to sperm or sperm components after disruption of the blood/testes barrier that is induced by vasectomy (see my other article on the immunologic effects of vasectomy).
There are many recent studies that report similar findings regarding testicular fibrosis and impairment of spermatogenesis after vasectomy. See this reference:
"METHODS: Testicular tissue was obtained by Trucut needle from men who had undergone a vasectomy >5 years previously or had OA from other causes and from fertile men during vasectomy. Seminiferous tubules were milked to measure sperm yields. Numbers of Sertoli cells and spermatids and thickness of the seminiferous tubule walls were assessed using quantitative computerized analysis. RESULTS and CONCLUSIONS: Sperm yields/g testis were significantly decreased in men post-vasectomy and in men with OA, relative to fertile men. Significant reductions were also observed in early (40%) and mature (29%) spermatid numbers and an increase of 31% was seen in the seminiferous tubule wall (basal membrane and collagen thickness) of vasectomized men compared with fertile men. Clinical pregnancy rates in couples who had had a vasectomy were also significantly reduced."
And this also:
"Vasectomy caused a significant decrease in germ cells in the later stages of spermatogenesis. A significant 2.7-fold increase in total (peritubular plus interstitial) fibrosis was observed, which showed a positive relationship with obstructive interval. CONCLUSION(S): Vasal obstruction results in significant reductions in germ cells in the later stages of spermatogenesis and increases in testicular fibrosis, both worsening with an increasing obstructive interval. Testicular damage after vasectomy might impact upon the prospects for reversal." Raleigh D, O'Donnell L, Southwick GJ, de Kretser DM, McLachlan RI. - Fertil Steril. 2004 Jun;81(6):1595-603.
And this one:
"RESULTS: A significant increase in interstitial fibrosis was observed along with the obstructive interval (p < 0.001). Interstitial fibrosis, but not the intraseminiferous status, reflects the irreversible damage of vasectomized testes." Aktuelle Urol. 2003 Jul;34(4):262-4.
And another:
"Testicular biopsy specimens from 21 consecutive men were obtained at vasovasostomy. Percent of interstitial fibrosis was determined quantitatively by NIH-image after Masson Trichrome staining. PCNA-labeling index (LI) was calculated on each testis. Interstitial fibrosis contributes to the irreversible damage of vasectomized testes." (Shiraishi K, Takihara H, Naito K. - Contraception. 2002 Mar;65(3):245-9.
Why should you care? Well, fibrotic scarring of the testes not only affects spermatogenesis (formation of sperm, which most vasectomized men don't care about), but can also affect the autocrine and paracrine (hormonal) functions of the testes. You see, the testes synthesize testosterone, the main male hormone. Testosterone is necessary for normal male function and sexual function (erection and libido).
Testosterone deficiency as one might expect with fibrotic scarring of the testes can cause symptoms of "andropause". What is andropause? See this reference:
Symptoms of Andropause (low testosterone levels)include fatigue, depression, irritability, reduced libido, awareness of premature ageing, aching and stiff joints in the hands and feet, increased sweating especially at night, and classic hot flushes. Last but not least, erectile dysfunction is common and reduced early morning erections are often an early warning sign. The age range of 31-80 (mean 54) is wider than that of the menopause in women (45-55) reflecting the importance of the wide range of factors influencing its onset. Associated factors appeared to be psychosocial stress, alcohol, injuries or operations, particularly vasectomy, medication side effects, smoking, obesity, infections (such as the orchitis caused by mumps and glandular fever, and prostatitis) and impaired descent of the testes.
Notice the mention of vasectomy as a factor in these men with symptoms of andropause. These symptoms strike at the heart of masculinity and can include: decrease in erectile potency, decreased libido, fatigue, and reduction in muscle mass and strength, change in fat deposition patterns (to that of women), poor concentration, irritability, and reduced bone mass.
The studies of testosterone levels after vasectomy have led to conflicting data. This is partly due to reliance on "normal ranges" that are very wide (300 to 1200 ng/dl) and lack of pre-vasectomy levels for comparison purposes, as well as lack of testing for free (bioavailable) testosterone levels. In addition, the studies that show transient increases in testosterone levels reflect damage as opposed to health, and declines in levels surely follow. How could a transient increase in testosterone levels after vasectomy reflect normal function? It is more likely a reflection of damage and after the inflammation subsides you are left with inadequate testicular function in some men.
So, vasectomy causes testicular damage, scarring, fibrosis, and inhibits spermatogenesis in some, but not all men. This can cause enough damage to induce relative decreases in serum testosterone and can cause the symptoms noted above. For example, say your pre-vasectomy total testosterone level is 600 (normal range 300ng/dl to 1200 ng/dl) and several years after vasectomy, it is 350. (still in the "normal range") Perhaps in your case, you would develop symptoms and require testosterone supplementation, for life. This seems like something that bears mention in the vasectomy consent process.
My purpose in writing this article is to inform men and their partners of some of the risks of vasectomy that are well represented in the medical literature, but are not mentioned in the vasectomy informed consent process. I think this is wrong. The idea that vasectomy has no effect on sexual function (libido, potency, and ejaculation) is not true for all men. If you did develop symptoms after vasectomy, you might be told it is "all in your head" or that "vasectomy can not do that". At the least, get your total and free testosterone levels checked before you accept this explanation.
If you are considering vasectomy, please read my website first, then you will not get any surprises. If the vasectomy informed consent process were complete and fair, I would not need to write these articles, but it is not generally and this is wrong. If after you accept all of the potential outcomes, you wish to proceed with vasectomy, good luck to you.