Nonvasectomized Men Research Articles

Pilot Study: Next-generation Sequencing of the Semen Microbiome in Vasectomized Versus Nonvasectomized Men

BackgroundApproximately half a million vasectomies are performed every year in the USA. There is a paucity of literature on the impact of male sterilization on the semen microbiome and whether it prompts microbiota dysbiosis. ObjectiveTo investigate if vasectomy induces changes in the seminal microbiome via comparison of semen samples from men before and after vasectomy, and if the seminal microbiome profiles for vasectomized men follow a particular pattern with respect to diversity and abundance. Design, setting, and participantsFrom July 2021 to February 2022, we prospectively collected and analyzed semen samples from 58 men at one outpatient clinic. Eighteen men provided a semen sample before and 3 mo after vasectomy. We also collected semen samples from 22 fertile nonvasectomized men and from a further 18 vasectomized men at 3 mo after vasectomy. Outcome measurements and statistical analysisSemen microbiome α-diversity, beta-diversity, and relative abundance were compared initially between paired and then between unpaired vasectomized and nonvasectomized samples. Analysis of variance (ANOVA), permutational multivariate ANOVA, and analysis of the composition of microbiomes with bias correction were used to assess differences. Results and limitationsIn both paired and unpaired sets of samples, a decreasing trend for α-diversity in semen after vasectomy was observed. Shannon diversity, the relative abundance of species with an abundance >2%, and composition were not significantly changed. Sphingomonas, Brevundimonas, and Paracoccus abundance decreased after vasectomy, while Corynebacterium abundance increased. The results may be limited by the sample size and lack of demographic heterogeneity. ConclusionsVasectomy is followed by a decrease in α-diversity and changes in the relative abundance of bacterial species in the semen microbiome. Further investigation is necessary to understand the clinical significance of these changes after vasectomy. Patient summaryWe evaluated changes in the bacteria species in semen after vasectomy. We found that vasectomy decreased the richness and evenness of bacteria species in semen, but the overall bacterial community remained similar. Further studies are needed to assess the implications of changes in semen bacteria after vasectomy.

Expression of the pro-inflammatory P2Y14 receptor in the non-vasectomized and vasectomized human epididymis.

Vasectomy causes spermatozoa accumulation in the epididymis, which may cause epididymitis. Inflammation is triggered by alert molecules released following tissue stress or injury. These include uracil-diphosphate glucose (UDP)-glucose, which activates the pro-inflammatory P2Y14 receptor (P2Y14), and induces immune cell recruitment. However, little is known about P2Y14 in the epididymis and its potential activation following vasectomy. (i) To localize P2Y14 in the human excurrent duct; and (ii) to examine the effect of vasectomy on P2Y14 protein and P2RY14 mRNA content, the production of selected cytokines and chemokines, and immune cell recruitment in the epididymis. In situ hybridization, qRT-PCR, western blotting, immunohistochemistry, and immunofluorescence were performed in banked human epididymis samples. P2RY14 mRNA and P2Y14 protein were detected in epithelial cells in the efferent duct, epididymis and vas deferens in non-vasectomized men. Keratin 5 (KRT5)-positive basal cells were strongly labeled for P2Y14 in all epididymal segments. A progressive apical localization was detected in principal cells (negative for the proton pump V-ATPase) from the corpus to the cauda. A subset of V-ATPase-positive clear cells also showed strong P2Y14 labeling. Vasectomy induced an increase in P2RY14 mRNA in the corpus and cauda, and stronger apical labeling in principal cells in the corpus. CXCL10 mRNA increased in the cauda and CCL2 mRNA decreased in the corpus of vasectomized versus non-vasectomized men. No change in IL-8 and IL-1β mRNA was detected. Numerous CD45+ leukocytes were detected in the interstitium of the corpus and cauda following vasectomy, while only a few were seen in non-vasectomized men. Several CD45+ leukocytes, some of which containing spermatozoa, were detected in the corpus lumen following vasectomy. Our study indicates that vasectomy-induced spermatozoa congestion may lead to an inflamed-prone local environment characterized by potential activation of P2Y14 and recruitment of immune cells in the epididymis.

Vasectomy and Prostate Cancer Risk: A 38-Year Nationwide Cohort Study.

A man's risk of prostate cancer has been linked to his prior reproductive history, with low sperm quality, low ejaculation frequency, and a low number of offspring being associated with increased prostate cancer risk. It is, however, highly controversial whether vasectomy, a common sterilization procedure for men, influences prostate cancer risk. We established a cohort of all Danish men (born between 1937 and 1996) and linked information on vasectomy, doctor visits, socioeconomic factors, and cancer from nationwide registries using unique personal identification numbers. Incidence risk ratios for prostate cancer by time since vasectomy and age at vasectomy during the follow-up were estimated using log-linear Poisson regression. Overall, 26238 cases of prostate cancer occurred among 2150162 Danish men during 53.4 million person-years of follow-up. Overall, vasectomized men had an increased risk of prostate cancer compared with nonvasectomized men (relative risk = 1.15, 95% confidence interval = 1.10 to 1.20). The increased risk of prostate cancer following vasectomy persisted for at least 30 years after the procedure and was observed regardless of age at vasectomy and cancer stage at diagnosis. Adjustment for the number of visits to the doctor and socioeconomic factors did not explain the association. Vasectomy is associated with a statistically significantly increased long-term risk of prostate cancer. The absolute increased risk following vasectomy is nevertheless small, but our finding supports a relationship between reproductive factors and prostate cancer risk.

Relationship between Vasectomy and Sexual Frequency.

Men who are considering vasectomy as a means of contraception may have significant anxiety about their future sexual potency. As a result, couples may choose other forms of contraception with lower efficacy. We sought to determine the relationship between vasectomy and the frequency of sexual intercourse. We analyzed data from cycles 6 (2002) to 7 (2006-2008) of the National Survey of Family Growth to compare the frequency of sexual intercourse of men who had undergone vasectomy with men who had not. Analysis was performed using data from male and female responders, and excluded men who had never had sex and those below age 25. We constructed a multivariate logistic regression model to adjust for demographic, socioeconomic, reproductive, and health factors. The main outcome measure was the sexual frequency in the last 4 weeks. Among male responders, a total of 5838 men met criteria for our study; 353 had undergone vasectomy. For vasectomized men, the average frequency of sexual intercourse was 5.9 times per month compared with 4.9 times for nonvasectomized men. After adjusting for age, marital status, race, education, health, body mass index, children, and income, vasectomized men had an 81% higher odds (95% confidence interval [CI] 6-201%) of having intercourse at least once a week compared with nonvasectomized men. A total number of 5211 female respondents reported 670 of their partners had undergone vasectomy. For partners of vasectomized men, the average frequency of intercourse was 6.3 times per month, compared with 6.0 times for partners of nonvasectomized men. After adjustment, women with vasectomized partners had a 46% higher odds (95% CI 5-103%) of having sexual intercourse at least once a week compared with women with nonvasectomized partners (P = 0.024). Vasectomy is not associated with decreased sexual frequency. This finding may be helpful to couples as they consider contraceptive options.

MP43-09 FAILURE TO ATTAIN STRETCHED PENILE LENGTH AFTER INTRACAVERNOSAL INJECTION OF A VASODILATOR AGENT IS PREDICTIVE OF VENO-OCCLUSIVE DYSFUNCTION ON PENILE DUPLEX DOPPLER ULTRASONOGRAPHY

INTRODUCTION AND OBJECTIVES: Men who are considering vasectomy as a means of contraception may harbor significant anxiety regarding their future sexual potency. As a result, couples may choose other forms of contraception with lower efficacy. While prior studies have demonstrated high satisfaction rates after vasectomy, no study to date has provided an objective measure of sexual function after vasectomy. Therefore we sought to determine the impact of vasectomy on the frequency of sexual intercourse. METHODS: We analyzed data from cycles 6 (2002) to 7 (20062008) of the National Survey of Family Growth (NSFG) to compare the frequency of sexual intercourse (within the prior 4 weeks) for men who had undergone vasectomy versus those who had not. We excluded men who had never had sex, as well as men under the age of 30, since vasectomy prior to this age is less common. We then constructed a multivariate logistic regression model to adjust for age, marital status, race, education, health, BMI, children, and income. RESULTS: A total number of 3798 men met the criteria for our study; 317 (8.3%) had undergone vasectomy. For men who had undergone vasectomy, the average frequency of sexual intercourse was 5.8 times per month compared to 4.8 times per month for nonvasectomized men. Only 6% of vasectomized men did not have sexual intercourse in the prior 4 weeks, compared to 16% of nonvasectomized men. In addition, 66% of vasectomized men and 53% of non-vasectomized men had sexual intercourse at least once a week. After adjusting for demographic, socioeconomic, reproductive, and health factors, men utilizing vasectomy had a 77% higher odds (95% CI 2-205%) of having sexual intercourse at least once a week, versus less than once a week. CONCLUSIONS: Vasectomy does not adversely impact sexual frequency. This finding may be helpful to couples as they consider their contraceptive options.

660 A COMPARATIVE ANALYSIS OF SEXUAL BEHAVIORS AND CONDOM USAGE OF VASECTOMIZED MEN

You have accessJournal of UrologyGeneral & Epidemiological Trends & Socioeconomics: Quality of Life1 Apr 2012660 A COMPARATIVE ANALYSIS OF SEXUAL BEHAVIORS AND CONDOM USAGE OF VASECTOMIZED MEN Vidit Sharma, Kunj R. Sheth, Sherwin Zargaroff, Brian Le, James M. Dupree, and Robert Brannigan Vidit SharmaVidit Sharma Chicago, IL More articles by this author , Kunj R. ShethKunj R. Sheth Chicago, IL More articles by this author , Sherwin ZargaroffSherwin Zargaroff Chicago, IL More articles by this author , Brian LeBrian Le Chicago, IL More articles by this author , James M. DupreeJames M. Dupree Chicago, IL More articles by this author , and Robert BranniganRobert Brannigan Chicago, IL More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.740AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Vasectomy is one of the most reliable and cost-effective forms of family planning available, explaining why an estimated 6% of American men choose it for their contraceptive needs. Yet, very little has been reported on how it influences the sexual behavior of men. Here we investigate sexual behaviors of vasectomized men compared to those who did not undergo the procedure. METHODS From 2006-2010, the Centers for Disease Control (CDC) conducted the National Survey for Family Growth sampling 10,403 men aged 15-45 on family planning attitudes and behaviors. Participants aged 25-45 were included in our study, and the probabilistic and clustered design of the survey was used to nationally extrapolate inferences. 368 vasectomized men were age-matched to 4048 non-vasectomized controls, translating to a total of 40,917,258 men nationally. Standard statistical methods were used to compare the age-adjusted sexual activity and condom usage between vasectomized and non-vasectomized men. Men with more than 1 sexual partner within a 3 month period were labeled as engaging in “promiscuous sexual behavior”. RESULTS Vasectomized men had a higher sexual frequency (6.6 vs 5.6, p=0.01) than non-vasectomized men within 4 weeks of the interview and were more likely to be married (85.2% vs 51.0%). 2.8% (103,412) of vasectomized men and 4.8% (1,944,479) of non-vasectomized men engaged in promiscuous sexual behavior. Of the vasectomized men engaging in promiscuous sexual behavior, 82.8% (85,673) did not use a condom compared to 41.9% (814,758) of non-vasectomized men during their recent sexual encounters. CONCLUSIONS We found that vasectomized men's sexual behaviors were significantly different than age-matched controls. As a whole, vasectomized men tend to have a higher sexual frequency, albeit with fewer partners. The vasectomized men who did engage in promiscuous sexual behavior were half as likely to use condoms. Given the sizeable population (85,673) of vasectomized men in this category, counseling efforts regarding condom use may have a significant impact on minimizing the propagation of sexually transmitted diseases. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e269 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Vidit Sharma Chicago, IL More articles by this author Kunj R. Sheth Chicago, IL More articles by this author Sherwin Zargaroff Chicago, IL More articles by this author Brian Le Chicago, IL More articles by this author James M. Dupree Chicago, IL More articles by this author Robert Brannigan Chicago, IL More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

(18)F-FDG Uptake of Human Testis on PET/CT: Correlation with Age, Sex Hormones, and Vasectomy.

The purpose of this study was to evaluate glucose metabolism of normal human testis on (18)F-FDG PET/CT and to assess possible correlations among age, the serum levels of sex hormones, and vasectomy. (18)F-FDG PET/CT was performed in 66 normal healthy men (50.8 ± 13.6years, range 22-81), and mean standard uptake values (SUV) of (18)F-FDG in testis and adductor muscle were measured. Testis-muscle SUV ratios (T/M ratios) were calculated. Serum levels of total testosterone, free testosterone, estradiol, and of sex-hormone binding globulin (SHBG) were measured. We searched for correlations between T/M ratios and age and the serum concentrations of sex hormones. (18)F-FDG PET/CT was also performed in 32 vasectomized men (55.7 ± 7.8years, range 38-71) and 52 nonvasectomized men (55.4 ± 11.6years, range 37-72). Mean SUVs of testis and adductor muscle were measured, and T/M ratios were calculated. A significant age-related decline was found in T/M ratio (r = -0.509, p < 0.0001). Serum levels of total testosterone and free testosterone were also found to be positively correlated with T/M ratio (r = 0.427, p = 0.0003; r = 0.435, p = 0.0003, respectively). The mean SUV and T/M ratio of vasectomized men were significantly lower than those of nonvasectomized men (p < 0.0378 and p = 0.0001, respectively). Glucose metabolism in the testis in an adult population was found to be correlated with age, serum sex hormone level, and vasectomy history. These results indicate that testicular (18)F-FDG uptake may have attributed to testicular function and testicular histology. Our findings may have important implications for the interpretation of testicular (18)F-FDG uptake in the normal adult population.

Prenatal diagnostics in TESA/PESA pregnancies in Denmark 1995-2007: a shift from invasive procedures to nuchal translucency examination

Evidently, children born after intracytoplasmic sperm injection (ICSI) are at an increased risk of having sex chromosomal abnormalities. Here we evaluate the change in methods used for prenatal diagnostics in patients having ICSI with epididymal or testicular sperm from the introduction of the procedure in 1995 until December 2007. Four hundred and fifty pregnancies resulted in the birth of 553 children. Of the Danish subpopulation 115 (34.2%) received nuchal translucency examination (NT) and 43 (12.8%) received invasive prenatal diagnostics (IPD). IPD was carried out in 11 out of 23 couples (48%) during the period 1995–1998. Since 2002, less than 10% chose to receive IPD. Twenty-one (57%) of 37 Danish women 37–44 years of age underwent IPD compared to only 22 (7.4%) of the 299 women less than 37 years of age (p < 0.001). Conversely, since 1999 the use of NT has gradually increased to a frequency of 88.9% in 2007. The partners of vasectomized men had significantly more often NT performed compared to those of non-vasectomized men. IPD were not otherwise associated with the etiology of azoospermia. This study documents a shift in prenatal diagnostics from IPD to NT for testicular sperm aspiration/percutaneous epididymal sperm aspiration (TESA/PESA) couples.

History of cryptorchidism and ejaculate volume as simple predictors for the presence of testicular sperm

Testicular volume, hormones, and growth factors are used as predictors of finding motile testicular sperm in azoospermic men. In this study, the possible predictive value of very simple parameters such as systematic history, clinical examination, and determination of ejaculate volume have been evaluated. Two-hundred and sixty-two consecutive non-vasectomized men with azoospermia/aspermia were evaluated by systematic history, clinical examination, ultrasonography of the scrotal content, and hormonal and genetic analyses. Hormonal analyses included, as a minimum, determination of follicular stimulating hormone (FSH), luteinizing hormone (LH), and testosterone, while genetic analyses included karyotyping and examination for cystic fibrosis transmembrane conductance regulator (CFTR) mutations and Y microdeletions.In seventy-six cases (29%) genetics was the most likely cause of azoospermia. For men with at least one CFTR mutation, motile sperm could be detected in 100% of 13 men with congenital bilateral absence of vasa deferentia (VD) but only in 44% of 18 with present VD. Ejaculate volumes were significantly lower (2.3 mL versus 3.6 mL) in 81 men with motile testicular sperm detected compared to 111 men without detectable motile sperm (p < 0.001; Student's t-test), and the difference was still significant after exclusion of men carrying a CFTR mutation. Based on the present data, an ejaculate volume of 2.5 mL was considered a useful threshold value. Furthermore, an inhomogeneous histological pattern with maturation of sperm in small islands isolated in tissue showing Sertoli cell only (SCO) pattern seems characteristic for men with a history of cryptorchidism (negative predictive value: 95%).In addition to FSH, testicular volume, and other endocrine factors, it is important to consider that very simple factors such as ejaculate volume and presence or absence of VD in men with CFTR mutations might be used as predictors according to the chance of finding motile testicular sperm. Evidence for a strong association between a history of cryptorchidism and an inhomogeneous histological pattern with maturation of sperm in islands in tissue presenting SCO pattern might indicate that multiple TESEs should be considered in men with a history of cryptorchidism.

Processing-independent analysis for pro-C-type natriuretic peptide

AbstractC-type natriuretic peptide (CNP) is expressed in several human tissues. We designed a specific processing-independent assay for proCNP-derived products and quantitated the concentrations in human seminal plasma from normal and vasectomized men. Antibodies were raised against the N-terminus of human proCNP 11–27. Samples were incubated with trypsin prior to immunoassay, which allows for the measurement of “total” proCNP irrespective of the degree of post-translational processing. Seminal plasma from normal young men and vasectomized men were collected and quantitated; the molecular heterogeneity was evaluated by gel chromatography. The antiserum displayed high binding affinity. Preanalytical trypsin treatment fully exposed the proCNP 11–27 epitope detected by the antiserum. Seminal plasma from healthy men (n=120) contained ~8-fold higher proCNP concentrations compared to blood plasma (range 104–933pmol/L, age 18–25years); gel chromatography suggested the presence of several molecular forms. Parameters associated to male fertility, proCNP concentrations in blood plasma and time of abstinence did not correlate to the seminal proCNP concentrations. Measurement in vasectomized men disclosed seminal proCNP concentrations similar to non-vasectomized men (range 107–705pmol/L, age 34–44years). Taken together, our new proCNP assay shows that proCNP is abundantly present in human seminal plasma and that seminal proCNP is secreted from the prostate gland and/or the seminal vesicles.

Are Sexual Problems More Common in Men who have had a Vasectomy? A Population-Based Study of Australian Men

It is not known whether sexual problems are currently more prevalent among men who have had a vasectomy compared with those who have not had a vasectomy. To investigate whether vasectomized men are more likely to report experiencing a range of sexual problems than nonvasectomized men and to assess their overall sexual and relationship satisfaction. A population-based survey of 3,390 Australian men's sexual experiences was conducted using computer-assisted telephone interviewing. Proportions of vasectomized and nonvasectomized men who: (i) reported a sexual problem for at least 1 month during the last 12 months; and (ii) rated their sexual and relationship satisfaction as either extremely satisfying or not extremely satisfying. Vasectomy was reported by 25.1% of men, almost 70% of whom were aged 40-59 years. Vasectomized men were more likely to be married, live in regional areas, and speak English at home. Having a vasectomy was not associated with any specific sexual problem, such as lacking interest in sex or taking too long to reach orgasm. Vasectomized men (10.8%) were slightly more likely than nonvasectomized men (8.2%) to report problems maintaining an erection, but this difference disappeared when age and other socio-demographic variations were taken into account. Although vasectomized men (33.7%) were just as likely as nonvasectomized men (33.0%) to be extremely satisfied sexually, they were significantly more likely to be extremely satisfied with their relationship overall (48.3% vs. 42.9%). Our findings suggest that sexual problems are no more prevalent among vasectomized men than they are among nonvasectomized men.

Etiology of Azoospermia in 100 Consecutive Nonvasectomized Men

Etiology of Azoospermia in 100 Consecutive Nonvasectomized Men

Etiology of azoospermia in 100 consecutive nonvasectomized men

History was taken systematically for 100 azoospermic, nonvasectomized men referred consecutively to a Danish fertility clinic. The men were examined by ultrasound, and their blood samples were analyzed for karyotype, Y microdeletions, and cystic fibrosis transmembrane conductance regulator gene mutations. In 29% of patients, the condition could be explained by genetic abnormalities; in 22%, by diseases or external influence; and in 27%, by former cryptorchidism. The azoospermic condition remained unexplained in only 22%.

Vasectomy and prostate cancer: a case-control study in India.

The role of vasectomy in the development of prostate cancer remains controversial. In particular, there has been concern about detection bias and confounding in the previously published epidemiological studies examining this hypothesis. With the goal of minimizing detection bias, we have evaluated the relation between vasectomy and prostate cancer in a population without routine prostate cancer screening. A case-control study consisting of 175 prostate cancer cases and 978 controls with cancer diagnoses other than prostate cancer was conducted at hospitals covered by the Bombay Cancer Registry in Bombay, India. History of vasectomy, demographic, and lifestyle factors were obtained by structured interview. Multiple logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). Standardizing by age, 8.7% of cases and 8.3% of controls had had a vasectomy. The OR for prostate cancer comparing men who had had a vasectomy to those who did not was 1.48 (95% CI: 0.80-2.72) controlling for age at diagnosis, smoking status, alcohol drinking, and other demographic and lifestyle factors. Risk of prostate cancer associated with vasectomy appeared to be higher among men who underwent vasectomy at least two decades prior to cancer diagnosis or who were at least 40 years old at vasectomy. Although not statistically significant, the results of this hospital-based case-control study are consistent with the hypothesis of a positive association between vasectomy and prostate cancer. Because routine prostate cancer screening is not common in this population, detection bias was unlikely to account for this association.

Vasectomy and Prostate Cancer: More Questions Than Answers

As many as 500,000 US men are believed to have had a vasectomy in 1991, and at least four million US couples of reproductive age depend upon the method. About 42 million couples worldwide also rely upon vasectomy for contraception. Concern arose in the family planning community in February 1993 when two studies published in the Journal of the American Medical Association reported that vasectomized men are at higher risk of developing prostate cancer compared to nonvasectomized men. Prostate cancer is the second most common cause of cancer death among American men. Vasectomy, however, is among the safest, most effective, and most acceptable of contraceptive methods. A link between vasectomy and prostate cancer could therefore have a serious negative impact upon vasectomy practice and upon overall contraceptive practice in the US. The National Institutes of Health convened a panel of experts in March 1993 to assess the likelihood of a relationship between vasectomy and prostate cancer and to make recommendations about any changes in vasectomy practice which may be needed. The panel concluded that there was insufficient basis for recommending a change in clinical and public health practice at that time, but that the debate must be resolved. To that end, epidemiologic and basic biological research are needed. The author reviews the background of the debate, early questions, and recent developments, and discusses future research.

Vasectomy, serum assays, and coronary heart disease symptoms and risk factors

We compared three serum assays (two antisperm antibody assays and one assay for circulating immune complexes) and a number of CHD-related variables in 69 vasectomized (V) and 126 non-vasectomized (NV) participants in the Portland Center for the Multiple Risk Factor Intervention Trial. Significant differences between the V and NV men were found in sperm agglutination (SA) and sperm immobilization (SI) titers, as well as in several CHD risk factors, symptoms, and treatments; men in the V group had higher titers for SA and SI, smoked more, and had lower diastolic and systolic blood pressure than men in the NV group. Differences between V and NV in SA and SI activity remained even after we controlled for any effects that CHD risk factors, symptoms, and treatments may have had on the serum assays. Antibody development tended to decrease with age-at-vasectomy and increase with time-post-vasectomy. In the case of SA the antibodies clearly increased with time-post-vasectomy.

Safety of protamine sulfate administration in vasectomized men

The majority of vasectomized men develop antibodies against different sperm antigens, including protamine. Due to the fact that salmon protamine is used clinically for heparin reversal and that a cross-reactivity has been observed between human and salmon protamine, vasectomized men may be at risk for adverse reactions to protamine sulfate. In order to explore this possibility, serum samples were analyzed for the presence of anti-sperm and anti-protamine antibodies in 20 vasectomized and 20 non-vasectomized men (controls) about to undergo major heart surgery requiring heparin reversal. The patients were closely monitored for any possible reaction following the injection of protamine. Anti-sperm antibodies were detected in the serum of 15 of the vasectomized men whereas only two of the non-vasectomized subjects had this type of antibody. Twenty-five percent of the vasectomized men presented with anti-protamine antibodies; in the control group, none of the patients had developed this type of antibody. Following the administration of protamine sulfate, none of the patients in either group showed any adverse reaction to the drug. It is concluded that vasectomized men are not at increased risk towards adverse reactions following the injection of protamine sulfate.

Vasectomy and Non-Fatal Acute Myocardial Infarction: A Hospital-Based Case-Control Study in Seoul, Korea

One hundred and sixty-three Korean men aged 35-64 who were admitted to a university-affiliated hospital diagnosed for the first time with acute myocardial infarction (AMI) were compared with 326 matched non-AMI patients hospitalized with a diagnosis considered unrelated to vasectomy. When other potentially confounding variables were controlled for, vasectomized men were found to be 2.6 times (adjusted odds ratio) more likely to have had an AMI as compared to the non-vasectomized men (95% CL: 1.1, 6.1). The adjusted odds ratio of AMI for subjects having had a vasectomy less than or equal to 9 years ago was the same as those who had a vasectomy greater than or equal to 15 years (OR = 2.5), although those who had had a vasectomy 10-14 years ago were associated with a higher odds ratio of 4.2. Among those subjects with vasectomies who were also cigarette-smokers and/or hypertensive, the risk of development of AMI increased multiplicatively compared with those with none of these conditions. We suspect that our finding of this positive association may be spurious due to possible bias introduced during selection of controls and during the process of data collection. Cancer patients may have been less likely to undergo an elective surgical procedure such as vasectomy prior to the admission. When multivariate analysis included only controls who were non-cancer patients (N = 241 controls), the adjusted odds ratio between vasectomy and hospitalization for AMI was reduced to 2.1, (95% CL: 0.8, 5.7), which is no longer statistically significant. When the analysis was further limited to only those control subjects admitted with a diagnosis of digestive system problems, the adjusted odds ratio was reduced to close to unity (1.1). Recognizing the importance of the study topic and the fact that all previous epidemiological studies showed no association between vasectomy and cardiovascular diseases, we urge further studies. A historical cohort study in the Korean setting is considered feasible and is recommended.

Plasma reproductive hormones in normal and vasectomized Chinese males.

Plasma reproductive hormones (testosterone, LH, FSH and prolactin) were measured in 298 normal healthy males aged 30-73 years from rural areas of Sichuan Province, People's Republic of China, and in 505 similar men vasectomized between 1 year and 25 years previously. Age-related increases in LH and FSH but not in testosterone or prolactin were noted in normal men. No adverse effects of vasectomy were observed apart from a 16% increase in mean LH levels in the vasectomized compared to non-vasectomized men of similar ages.

Vasectomy and Vasovasostomy have no Effect on Seminal Plasma Zinc Concentrations

Mean zinc concentrations were determined for human seminal plasma obtained from 110 nonvasectomized men (139μg. per ml.), 43 recently vasectomized men (144μg. per ml.), 25 long-term vasectomized men (139μg. per ml.) and 25 men who had undergone vasovasostomy (129μg. per ml.). The results indicate that there is no significant short-term or long-term effect of these surgical procedures on prostatic secretory function as measured by seminal plasma zinc concentration.