Tony #3's experience - added February 8, 2009
The worst decision I ever made
When I began to read information about vasectomy after the birth of our third child, I found a lot of information on the Internet. I read the descriptions on "official" websites first (WebMD, The American Urology Association website, etc.) and found the procedure described in detail. There were some complications mentioned, but no mention of the physical effects of these complications on the small percentage afflicted. I looked at other websites and thought the wording of the information was like an advertisement for a new car or what you might see in the back of a magazine for a product of dubious value. This "hype" or "overselling" of the procedure felt disingenuous to me, and I continued my research, feeling as I wanted to know more about the risks, and less about the "facts" that stated there were essentially few or no side effects of consequence acutely or long after the procedure. I was not used to this type of advertising for a medical procedure and I felt as though the ads were designed to overcome male fears of surgery on their genitals in a paternalistic way, as if men could not really choose, but needed to be reassured excessively about their "unrealistic fears" regarding the procedure affecting their manhood or sexuality. The ads seemed like those written to convince mothers that all vaccines are safe. I am a fan of ads that list the good, the bad, and the ugly. Hope for the best, plan for the worst I always say.
During my research, qualifiers such as, "transient" or "minor" followed the side effect descriptions, and there seemed to be an inordinate focus on alleviating fear and anxiety over "vasectomy myths". The myths seemed to include any change in sexual function and any long-term risks, health consequences or safety issues. I found lists of these myths online and wondered if they were all myths. One "myth" I saw repeatedly was that vasectomy couldn't cause a change in the ejaculate. This outcome was described away as unlikely based on sperm only making up 0.2% of the ejaculate. The information did not mention the studies that I've since read that show a decrease in prostatic secretions after vasectomy or studies that prove a 40% decrease in ejaculate volume after vasectomy on average. I've also since read that during vasectomy, many nerves that travel along with the vas can be injured. This is never mentioned. Many nerves exert a trophic influence on the target organ and if these nerves are damaged or transected, there are effects on the function of the target organ.
It seemed as if men were pre-judged as not able to handle the truth, so the information was not entirely honest or at least only described the most likely outcomes. So if you did develop a change in ejaculation, it must be you in particular. It would be fairer to say that some men experience a decrease in ejaculate volume, propulsive force, or even retrograde ejaculation (into the bladder) after vasectomy, and if this would bother you, vasectomy may not be for you as there is no treatment for this if it occurs. I think men need to know all potential outcomes that can affect quality of life, not just those that someone else thinks are important. My point is all possible outcomes and their possible effects on health or quality of life should be mentioned, especially for an elective procedure designed to treat a non-medical issue (fertility).
Another "myth" I saw had to do with orgasmic sensation. "It will not be affected" was again the claim I read. Anecdotally, there are men who complain of this as noted below. I have read many posts online (frequently made anonymously online in men's health forums) that describe changes in ejaculation and orgasmic sensation after vasectomy. Here are a few:
"When I had my vasectomy, I actually noticed a spike in sex drive three or four weeks after the procedure, but within three months I was experiencing much of what other posters here are describing: weak erections and ejaculations, going from near-daily morning erections to none, even an increase in the softness of my skin."
"Since my vasectomy (2 years ago) I have felt a total lack of satisfaction after sex and do not have any feeling during orgasm. Can't say my sex drive has reduced though. It feels like I haven't had sex since my operation. Whatever they may say about there only being about 2 percent of sperm in an ejaculation the body seems to have a kind of fuel gauge built into the testicles. These are not getting emptied and therefore I get no sense of release from sex. There seems to be a lot of similar cases to mine and I can assure you it is a physical, not mental problem any couch could fix."
"My husband had a vasectomy about a month ago and while, thankfully, he is not experiencing the chronic pain that is mentioned in this forum, he is having trouble of different sort. He says that his arousal is normal, sex is normal, and the amount of ejaculate is normal; however, when he climaxes, it is much less intense. He is a psychologist and keeps himself extremely healthy both physically and mentally. He said that during sex, there is no build up anymore. He just has a spontaneous orgasm with no warning. It just happens suddenly and build up that typically accompanies an orgasm is no longer there. It is incredibly frustrating because our sex life has always been incredible."
"And here I thought I was all alone, I have pretty much the same problem as most of you. The sex is great, here comes the orgasm, here it comes...wait for it....here we go!!! OK so it's over what the hell happened? I had my vasectomy 3 years ago and sex has not been the same since so don't tell me I need more time to recover...Great hey I'm only 30 now, what a sex life to look forward to in the future."
"I just located this site while I was searching to find out if other men had the same problem I had and it appears they do. I have a very noticeable decrease in orgasm pleasure (sometimes I am unaware that I had one). It has been about a month since my procedure and it was uneventful but now where I used to have a very high sex drive and could never get enough sex the diminished pleasure of orgasm makes sex feel like too much work for to little return. I am only 38 and the prospect of this being "as good as it's going to get" is very depressing."
The men who made these statements are ruined sexually. This outcome should be studied, quantified, and added to the list of potential vasectomy poor outcomes for men to weigh in choosing vasectomy. I was lucky enough to miss out on this particular complication. All of these men would have to be very surprised, as this outcome is not mentioned in any of the consent documents I've ever seen. The study of this outcome does not garner the same interest as studies on vasectomy failure (pregnancy rate after vasectomy). Why not? I'd rather have an unintended pregnancy than lose all orgasmic or sexual pleasure.
I saw quotes like: "Although complications such as swelling, bruising, inflammation, and infection may occur, they are relatively uncommon and almost never serious." I also found out that infection or bleeding issues after vasectomy occur in 2 to 5% of patients. (Source: Vasectomy-Information.com) Some of these men require surgery for hematoma (blood collections) or for abscesses (collections of pus due to infection). The affected men probably didn't find it to be "never serious".
See this post from a vasectomy forum:
"I had the procedure and on the way home to recover I began to feel pain and swelling in my scrotum. The swelling became very intense to the point that I could feel them pushing on the inside of my legs. At first I thought that this might be normal after the procedure. By the time I made it up to the house I was waddling like a duck. I laid down on the bed and told my wife "Call the doctor; something's not right here ". The doctor said to meet him at the emergency room. He told me I had a hematoma. I was still swelling and by the time I got to the hospital and my scrotum was softball size. The doctor arrived and said it's been 25 yrs since he's seen anything like this. I was not very reassured at this point. He's said an artery was cut and he would have to open me up and connect it to stop the bleeding. They knocked me out and brought me into surgery. I woke up sick to my stomach and in severe pain. I had a tube sticking out of my scrotum for drainage and had some kind of scrotal support (jock strap) on wrapped up in bandages and gauze. I was in bed for nine days straight in agonizing pain. Just to make it to the bathroom was a task of a lifetime. I would begin shaking uncontrollably to the point I was calling for my momma."
The sites that focused on chronic testicular pain or "post-vasectomy pain syndrome" frightened me even more. I decided not to have the procedure done, as sex was a very big part of my life. I was and still am married to a beautiful woman and the idea that I could have a change in sexual function was too scary to risk. I wished my wife had decided to have a tubal after our third child, but she is a very holistic person and did not believe in surgery unless it was absolutely necessary and she had already had two cesarean sections. Little did I know her "no surgery" perspective was one I should have adopted.
Fast-forward about two years. Now I'm 43 years old. My wife and I felt like a pregnancy was unlikely given our previous difficulty getting pregnant and the fact that we were both over forty. Then a trip to Mexico, a lot of sun and beer, and some "quality" couple time later, and we found out we were wrong and were expecting our fourth child. This meant a third cesarean section for my wife and an unplanned and unexpected addition to our already fairly large brood. We only had a three-bedroom house.
After the birth of our fourth child (the only boy, whom I love dearly and am glad for), the issue of what to do to prevent number five came up again. I began my research in earnest again and ended up back in the same place. Since I enjoy having an unrestricted orgasm with my wife, (read orgasm directly into the vagina) it seemed condoms for a decade until menopause, or a vasectomy were my choices. I was seriously considering vasectomy again. I started researching the idea again. The rise of the "no scalpel, open" vasectomy was new and I read more about it. I began to get excited as my research had led me to a "new and better vasectomy method" with fewer side effects. Wasn't I the smart consumer? I actually thought I was.
I did further research and adverse events were always minimized again as if to placate the reader, as if he were a child. For example: "A major study of vasectomy side effects occurring within 8 to 10 years after the procedure was published in the British Medical Journal in 1992. Investigators questioned 10,590 vasectomized men, and an equal number of non-vasectomized men, to determine if they had developed any of 99 different disorders. After a total of 182,000 person-years of follow-up, only one condition, epididymitis/orchitis (defined as painful, swollen, and tender epididymus or testis)--was found to be more common after vasectomy. This local inflammation most often occurs during the first year after surgery. Treated with heat, the condition usually clears within a week." (This is not really true for a lot of men.)
It turns out that a study existed that showed congestive (not infectious) epididymitis occurred in about 6% of men who had a "closed" vasectomy and in about 2% of men who had an "open" vasectomy. The closed versus open descriptor refers to whether the testicular end of the vas deferens (tube that carries sperm from the testes to the ejaculatory duct) is left closed or open.
"This study was done to determine if there was a difference in results when both vas ends were closed or when the prostatic end was closed and the testicular end left open. The author performed 6220 vasectomies between June 1, 1972 and June 1, 1992. The first series consisted of 3081 vasectomies in which both ends of the vas deferens were closed. The second series consisted of 3139 vasectomies in which the testicular end of the vas deferens was left open while the prostatic end only was closed. No portion of the vas was excised. Congestive epididymitis was diagnosed in 6% of cases utilizing closed-end vasectomy and 2% of cases where the open-end vasectomy was performed. Open-end vasectomy is recommended because the incidence of congestive epididymitis is reduced." (Moss, WM)
This study helped me worry less and made me lean toward an "open" vasectomy, but I later found out that the statistics from this study weren't based on 6220 cases, but 10% of the overall cases. The study did not follow men over time long enough to see if any developed chronic problems either. The study doesn't say what can happens after you develop congestive epididymitis and it leads to post-vasectomy pain syndrome (PVPS didn't even exist as a concept when this study was done.) For some men, the pain symptoms do not respond to warm baths and anti-inflammatory medicine (the prescribed treatment) and can become chronic and affect quality of life and sexual function. (The numbers on this vary, but seem to be up to 2-5% of all vasectomized men.) Some of them require vasectomy reversal or removal of the epididymus and even these treatments aren't always effective in relieving the pain.
See these medical abstracts:
"RESULTS: Mean time to pain onset after vasectomy was 2 years. Presenting symptoms included testicular pain in 9 cases, epididymal pain in 2, pain at ejaculation in 4 and pain during intercourse in 8. Physical examination demonstrated tender epididymides in 6 men, full epididymides in 6, a tender vasectomy site in 4 and a palpable nodule in 4. No patient had testicular tenderness on palpation. Unilateral and bilateral vasovasostomy was performed in 3 and 10 of the 13 patients, respectively. Postoperatively 9 of the 13 men (69%) became completely pain-free."
"Fifteen epididymectomies were performed on 10 patients with post-vasectomy pain and 12 specimens were available for histopathological review. The findings were compared with those in 2 groups in which epididymectomy was performed for chronic epididymo-orchitis and epididymal cysts. The results showed that 50% of the post-vasectomy group were cured by simple epididymectomy. Pathological findings revealed features of long-standing obstruction and interstitial and perineural fibrosis which may have accounted for the pain."
You see, the consents and brochures do not mention you might need further surgery if you are in the group with persistent symptoms of pain (The incidence of PVPS was listed as 1 in 2000 on my vasectomy consent, which I now know is absolutely false.) There are no known risk factors for PVPS except perhaps high pre-vasectomy sperm count and no one tests your pre-vasectomy sperm count to tell you that you have higher risk. Again, no research to identify men at risk has been done as the condition is considered to be extremely rare and perhaps psychological. I can tell you my symptoms were not psychological. It is hard to feign sharp jabbing testicular pain or a constant dull ache that radiates into the groin. Most of the men I have spoken with who developed PVPS were smart, relatively successful men with no past psychiatric history.
Herein lies the difficulty of these statistics. The statistics are reassuring, unless you are the affected patient. The stories can be blown off as rare and unlikely. The low incidence is also reassuring because there is little detail as to how the resultant difficulty affects a given patient. Where is the information about the six percent of men who have to seek medical treatment for these complications and the psychological effects of trouble with sexual response or genital pain? It would be fair to say: "If one develops any bleeding, infection, or pain that requires surgical intervention, it can be very distressing due to the anatomical areas involved." Alternatively, "Since the orgasmic response and sexual response is very complex and is affected by pain or anxiety, some of these men could have changes in sexual function or enjoyment."
Needless to say these statistics and stories were a bit "off-putting", but somehow after I talked to a group of friends and male coworkers, I convinced myself I would not end up like these unfortunates. I was in excellent health, an age group ace runner, and an aspiring triathlete with no medical issues. So I found a surgeon with vast experience (he had performed over 17,000 vasectomies and taught other doctors on three continents how to do the "no scalpel, open" technique), and bit the bullet, so to speak. It turned out to be the worst decision of my life. The idea that it is the surgeon's skill that makes the difference was turned upside down for me. I truly believe it is just luck as to how it turns out for a given man. Now, after all my research, I also believe the autoimmune response after vasectomy is genetically unique from one man to the next and this contributes to the amount of scarring and fibrosis after the procedure.
I have had pain from soon after the procedure (4/07) until the present, and the symptoms not only persisted, but also worsened over time. I contacted the doctor who did the procedure and he adopted a "watch and wait" approach for the first six months. (This is not defensible based on my subsequent research.) I was afraid of additional surgery, so despite the ongoing discomfort, I felt it was a reasonable approach as the symptoms were tolerable with frequent use of Motrin. At that time, I also knew little about post-vasectomy pain syndrome. As things continued to worsen and began to affect my focus at work and markedly affect my quality of life, I felt as though further "waiting" was a poor idea. I contacted the doctor again and he discussed "resecting the vasectomy sites" as a treatment plan. He did not mention reversal, (the procedure with the best treatment response if conservative treatment fails), until I brought it up, and then he agreed it might be warranted. I found out later that he had done four other reversals for pain, but he never mentioned the diagnosis of PVPS. I opted for reversal as the prospect of continuing pain was rather daunting, and I hoped to get back to my former "happy, pain-free self" as soon as possible. All conservative treatment had failed and I wanted my life back. I had already lost the pleasure in life for a year. I couldn't have cared less about becoming fertile again, I just wanted to be normal again.
My symptoms included:
1) Pains near the lower part of the testicles or in the tail of the epididymus - This had been there for at least 10 to 12 months and had stopped me from riding my bike. It was a localized sharp needle or ground glass sensation under my scrotum bilaterally. Even by itself this would have required surgical treatment have as it affected sleep and made long car rides a challenge. (I commute an hour each way to and from work.) I now believe this pain was due to fibrotic back-pressure related scarring in the tail of the epididymus bilaterally. This pain has not totally resolved with vasectomy reversal.
2) A constant dull ache in the testes, similar to what many men feel if they have no sex for weeks but more intense. The reversal center spokesperson I contacted said their facility had seen some men who got a reversal just for this "weird full feeling" in the genital region, mostly in the testicular area. This sensation was not tolerable to me and is a distraction at the least. It began in the week after surgery and sometimes seemed less noticeable if I took Motrin. Taking Motrin on a long-term basis every day adds risks that I was not willing to take with my stomach and kidneys, however. In addition, chronic discomfort in the testes tends to affect ones mood, quality of life, and sexual function.
3) The most troubling problem was the appearance of scar tissue (induration) on the right side near the epididymus associated with a fibrotic feeling to a part of the vas there. This occurred at 13 months post-vasectomy. Unfortunately for me, this had begun to pull on spermatic cord structures (nerves) and had caused a chronic low-level "rupture" feeling that radiated into my groin and abdomen. I was most worried about this because I was not sure a reversal would relieve this. Some unfortunate folks I had spoken to had to have the epididymus and obstructed vas removed. I hoped for the most conservative surgical approach. I lost ten pounds in two weeks due to anxiety, pain, and nausea from the radiating groin pain.
4) The inevitable guarding of my "area" keeps my three youngest children off my lap or is endured with anxiety. Pain in the testicles during sex tends to put a damper on the experience. Sorry to be so graphic, but I want to illustrate why I was willing to undergo a three to four hour corrective surgery on my genitals. Clearly, I did not want further surgery and waited for over a year.
5) The right testis always ached and the epididymus on that side became swollen and tender. I went to a local urologist who confirmed this in 4/08. (Dr. Terrence Frank in Lansing, MI) When I had sex, this pain would worsen and become difficult to tolerate for several days, which needless to say, negatively affected my sexual enjoyment and made me begin to avoid sex. It had become an intolerable situation. When I got an erection, the scar tissue on the right side would cause my testicle to rotate outwards as the testes are pulled up toward the body with erection. This would then cause severe pain and made sex completely useless.
Prior to my decision to have a vasectomy, I read all the information I could find and did notice the first two issues were mentioned, but were described as rare or trivial. I did not know of the significant possibility of chronic orchalgia (testicular pain) that could affect quality of life. I now know it affects up to 15 % of patients. I also was unaware of the possibility of number five above and certainly did not think I could become someone who avoided sex due to pain. For a fairly young man in his forties to avoid sex due to post-vasectomy pain was an outcome I could never have imagined.
I pursued a reversal and hoped that all these pain issues would be addressed. Time will tell. As you can see from the web, most men do fine after vasectomy. Less than ten percent regret having it and perhaps only two to five percent end up like me. The reversal surgery is successful in treating the pain symptoms in around 70% of patients. I felt that since my complications were clearly life altering and conservative treatment and time had not resolved the problem, surgery was my only option.
A board certified urologist did my reversal. He had completed a fellowship in microsurgery. He was a "super specialist" in reversal surgery. I found out that success rates for this type of surgery are very much dependent on the surgeon's skill and experience. In addition, having surgery on ones genitals is not like having any other surgery, and I was looking for "the best surgeon" who also had experience with vasectomy reversal for pain, not for fertility. The surgery was not covered by insurance and cost $8200 plus airfare and lodging. It took over three hours and was done with local anesthesia. I hope it is successful in returning me to my old asymptomatic self. Certainly, insurance coverage for a surgical procedure should imply coverage for any severe complications from the original covered procedure. It did not seem feasible for example, to cover tubal ligation or vasectomy and then not provide benefits for known complications from the covered procedure. The paperwork from the surgeon's office listed the diagnostic code as "Post vasectomy pain". My right epididymus was persistently swollen, tender, and painful and the pain would become excruciating when I got an erection or tried to have sex as noted above. Neither of these conditions, when clearly related to vasectomy have any curative treatment other than reversal after conservative treatment fails.
The months from April 2007 to August of 2008 have been the worst of my entire life. I would give the last ten years of my life to go back to April and not have the vasectomy. I have written to the American Urological Association requesting better consent practices for vasectomy. I have done extensive research since my poor outcome that have convinced me that vasectomy consent is a flawed procedure that is designed to placate men instead of educate them. I have written several articles to warn men of the risks, but they will, like me, choose for themselves and hope they are not in the unfortunate few.
After my extensive research, I do have new concerns about the procedure that have not made it into the vasectomy consent process. I had read this online: "Vasectomy does not affect your hormones, orgasm or ejaculation so there is no reason for it to have a negative impact on your sex life." Does Vasectomy affect a man sexually? Seems a fair question. Here is what you will read: "Not at all. Vasectomy has no effect on the production or release of testosterone, the male hormone responsible for a man's sex drive, beard, deep voice, and other masculine traits." Well, again, this may not be entirely true. Vasectomy causes testicular fibrosis (scarring) and this could cause changes in testosterone levels and cause symptoms of hypogonadism (andropause). See my other article: "Vasectomy Causes Testicular Damage". The medical literature on testosterone levels after vasectomy is inconsistent. 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 (inflammation) as opposed to health, and declines in levels likely follow. How could a transient increase in testosterone levels after vasectomy reflect normal function? It is more likely a reflection of damage due to inflammation. (This is seen in other glandular organs when they are inflamed such as the thyroid gland, and after the inflammation resolves, the person is hypothyroid.)
Prospective vasectomy candidates should be told of the extensive research showing testicular fibrosis in all vasectomized mammalian species studied to date, including humans. Fibrosis is essentially scar tissue and must have an effect on the function of the testes. The testes have two main functions: Production of sperm and production of sexual hormones (primarily testosterone). The human studies do show a decrease in spermatogenesis reflecting testicular damage. Sertoli cell support of spermatogenesis has been implicated in this pathology as has pressure induced changes from obstruction by closing off the vas deferens via vasectomy. This should not be surprising as men with obstructive azoospermia show similar testicular pathology associated with obstruction: 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. Hum Reprod. 2005 Oct;20(10):2795-800. Epub 2005 Jun 15
Why should you care if sperm production is damaged or you develop fibrotic scarring in the testes? The testes produce testosterone, and a relative decline in testosterone levels can cause decrease in erectile potency, decreased libido, fatigue, reduction in muscle mass and strength, change in fat deposition patterns (to that of women), poor concentration, irritability, and reduced bone mass.
I believe vasectomy causes testicular fibrosis and damages Sertoli cells affecting spermatogenesis. The damage to the testes from obstruction or via immunologic effects may cause earlier "andropause" via relative declines in testosterone causing symptoms of hypogonadism in some men. The total serum testosterone may still be in the "normal" range of 300 to 1200 ng/dl, but a significant decline within the range can still cause symptoms.
The study cited below from the medical literature shows biopsy proven interstitial fibrosis. The possibility that fibrosis (scarring) has no effect on testicular function is implausible. The hypothesis that similar changes seen in all mammalian studies to date are not in any way applicable to humans also seems unsustainable and represents some measure of "denial."
"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." Fertil Steril. 2004 Jun;81(6):1595-603
The damage to the testes from obstruction or via immunologic effects may cause earlier "andropause" via relative declines in testosterone causing symptoms of hypogonadism in some men. The total serum testosterone may still be in the "normal" range of 300 to 1200 ng/dl, but a significant decline within the range can still cause symptoms. If this happened, you could develop erectile potency issues and other symptoms. (i.e. irritability, decreased muscle mass, decreased libido, depressed mood, changes in fat distribution to that of women, poor concentration)
I personally experienced this side effect also, despite my reversal. My free and total testosterone levels dropped to the levels of a seventy year old and I developed many of the symptoms listed above. I am now dependent on Testim (testosterone) gel to relieve these symptoms. Symptomatic hypogonadism is extremely rare in a healthy 44 year old, and so, I relate it to my vasectomy. The fact that my left testicle is smaller on ultrasound (done at the same facility and by the same technician as one prior to vasectomy) also indicates to me that vasectomy has caused fibrotic scarring in my left testicle.
You might find this sort of blanket statement about vasectomy: "The operation also has no effect on sexuality. Erections, climaxes, and the amount of ejaculate remain the same. Occasionally, a man may experience sexual difficulties after vasectomy, but these almost always have an emotional basis and can usually be alleviated with counseling. More often, men who have undergone the procedure, and their partners, find that sex is more spontaneous and enjoyable once they are freed from concerns about contraception and accidental pregnancy."
Again, this is not true for all men and the idea that if you do have some noticeable change, it "almost always has an emotional basis and can be alleviated with counseling" is a strange statement with little research basis. I am a psychiatrist and have never seen a patient seeking counseling for emotionally induced sexual dysfunction after vasectomy. I have never even seen a mention of this issue in twenty years of seeing psychiatric patients and reading psychiatric journals. It is more instructive to look at what happens anatomically when vasectomy is performed. There is a study in the medical literature showing that 50% of the nerves that travel with the vas deferens (in the spermatic cord) are cut during vasectomy. These were the actual vas deferens (tubes that are cut) specimens from cadavers of vasectomized men.
"Quantitatively, the mean number of nerves per cross-section was about 1/2 of the number in spermatic cords; the total area of nerves resected on average during vasectomy amounted to nearly 50% of all nerves found near the vas in spermatic cords. This nerve resection could result in poor functional results after reversal of sterilization because the powerful contractions of the proximal vas deferens would be lacking." Pabst, et al 1979.
In another study, the changes in the complex innervations of the vas deferens (tubes) were destroyed by vasectomy. "Vas deferens specimens taken from 43 men during vasovasostomy were examined by histochemical techniques and electron microscopy for evidence of noradrenergic and acetylcholinergic nerve structures. The subjects had been vasectomized 1-15 years ago (mean 6.5 years). Controls were 22 men being operated for vasectomy. Light microscopy revealed fine noradrenergic nerve plexi throughout the muscle coat, in the proximal, urethral portions of the vas, and circling blood vessels in the adventitia, as well as in both proximal and distal control specimens. The distal, testicular specimens of previously vasectomized men contained only occasional adrenergic fibers. In proximal or urethral portions, fine cholinergic nerves occurred in the muscle coat; large ones in the adventitia near blood vessels, and numerous cholinergic fibers were located under the epithelium. In distal, testicular portions, cholinergic nerves were similar to controls and to urethral specimens from vasectomized men in the muscle layer only, but absent in lamina propria. Ultramicroscopic structure of these various nerve fibers is described in detail. It is to be noted that the distal portion of the vas is the testicular portion, as concerns innervation, and this is lost after vasectomy. It was remarkable to see evidence of reinnervation of cholinergic axons distally, however. It has been established that noradrenergic control is important for the motor and secretory activities of the vas. Physiological significance of adrenergic innervation is unknown. These results add evidence for the advice to men seeking vasectomy to consider it a permanent form of fertility control" (in other words, you can't go back to the way you were).
It seems plausible that if you cut these nerves, a change in function could occur. There are also studies that show a decrease in prostatic secretions after vasectomy, but no mention of this is made in pre-vasectomy counseling. See this abstract: "The seminal plasma constituents of acid phosphatase, maltase, citric acid, prolactin, zinc and magnesium were measured in men vasectomized for 1-8 years. Compared with values obtained for a group of normal fertile men, all the constituents, except acid phosphatase which was unchanged, decreased significantly after vasectomy, but not progressively so. Since the constituents measured are believed to be of prostatic origin, the results suggest that vasectomy in men decreases the secretory function of the prostate gland." In doing research about the procedure or reading brochures you will only see that phrase "no change will occur in ejaculation". Look at this abstract:
"In 56 males, vasectomized 8 years previously, and in 56 age-matched non-vasectomized controls, a number of secretory products of prostatic, seminal vesicular and epididymal/testicular origin were used to monitor post-operative changes in accessory sex gland function. Significant reductions were observed in seminal plasma volume (3.0 vs 4.9 ml, P less than 0.01), and the total ejaculate contents of zinc (5.1 vs 9.7 mumol, P less than 0.01), magnesium (10.6 vs 26.5 mumol, P less than 0.01), PAP (371 vs 1260 IU, P less than 0.005) and citric acid (76.7 vs 127.9 mumol, P less than 0.05), indicating a major impact on secretions of prostatic origin."