The Effect of Male Age Over 50 Years on Vasectomy Reversal Outcomes.

OBJECTIVE: Advancing paternal age is associated with impaired semen parameters. We sought to evaluate reproductive outcomes in men undergoing vasectomy reversal (VR) aged ≥50 vs <50 years. METHODS: Reproductive outcomes (obstructive interval, female age, anastomosis type, post-VR total motile count (TMC), and pregnancy) after VR were assessed for men aged <50 and ≥50 years. Statistical analysis was performed using Kruskal-Wallis rank sum or Chi-squared tests. Multiple logistic regression was used to identify factors associated with achieving pregnancy. RESULTS: A total of 2777 men <50 years and 353 men ≥50 years were included. The mean obstructive interval was 8.7 years less for men <50 years (8.9 vs 17.6 years, P <.001). The chances of needing a vasoepididymostomy were higher in men ≥50 years (19.5% vs 10.1%, P <.001). Post-VR total motile count was higher in men <50 years (59.3 vs 29.1 × 106/mL, P <.001). About 33.4% of men <50 years and 26.1% ≥50 years contributed to a pregnancy (P = .007). On multiple logistic regression analysis, obstructive interval <10 years (OR 1.295, P = .002) and female age <35 (OR 1.659, P <.001) were associated with achieving a pregnancy. A history of smoking was associated with decreased odds of achieving a pregnancy (OR 0.523, P <.001). Age <50 or ≥50 years at VR was not associated with achieving pregnancy (OR 0.852, P = 0.254). CONCLUSION: Compared to those ≥50 years, more men <50 years achieved a pregnancy after VR. However, on adjusted multivariable analysis, age at VR was not an independent predictor of achieving pregnancy. Shorter obstructive interval and female age were associated with achieving pregnancy, while a history of smoking was associated with decreased odds. Successful outcomes after VR can be achieved in older men, and VR should be considered in men ≥50 years, when performed by a trained microsurgeon.

Vasectomy and vasectomy reversals, active component, U.S. Armed Forces, 2000-2017.

During 2000-2017, a total of 170,878 active component service members underwent a first-occurring vasectomy, for a crude overall incidence rate of 8.6 cases per 1,000 person-years (p-yrs). The most common operative procedure performed was conventional vasectomy (99.2%), with less than 1% of vasectomies categorized as minimally invasive vasectomy. Among the men who underwent incident vasectomy, 2.2% had another vasectomy performed during the surveillance period. Compared to their respective counterparts, the overall rates of vasectomy were highest among service men aged 30-39 years, non-Hispanic whites, married men, and those in pilot/air crew occupations. Male Air Force members had the highest overall incidence of vasectomy and men in the Marine Corps, the lowest. Crude annual vasectomy rates among service men increased slightly between 2000 and 2017. The largest increases in rates over the 18-year period occurred among service men aged 35-49 years and among men working as pilots/air crew. Among those who underwent vasectomy, 1.8% also had at least 1 vasectomy reversal during the surveillance period. The likelihood of vasectomy reversal decreased with advancing age. Non-Hispanic black and Hispanic service men were more likely than those of other race/ethnicity groups to undergo vasectomy reversals.

Changes in the incidence and uptake of reproductive surgery versus in vitro fertilisation in Australia between 2001 and 2015: A population-based study.

OBJECTIVE: Improvements in success rates of assisted reproduction led to predictions that infertility surgery in both women and men would become extinct in developed countries. We sought to identify the changes in reproductive surgery that occurred between 2001 and 2015 to determine whether these predictions have been accurate. DESIGN: The Australian Institute of Health and Welfare (AIHW) national procedural dataset and the Australian Medicare Benefits Scheme (MBS) claims database were searched for procedure data for male and female reproductive surgery and assisted reproduction from January 2001 to December 2015. The denominators were based on annual point estimates of the total population aged 25-44 years (female) and 25-55 years (male) from the Australian Bureau of Statistics (ABS). This dataset provides procedures undertaken but not their indications. RESULTS: Over the study period the incidence of tubal surgery fell by 66%, vasectomy reversal by 33%, and surgical varicocoelectomy by 50%. In contrast, the rate of hysteroscopic myomectomy increased by 48%, hysteroscopic septoplasty by 125%, and laparoscopy for severe endometriosis increased by 84%. In vitro fertilisation oocyte retrievals increased by 90%. The rate of abdominal myomectomy was unchanged. CONCLUSION: Fertility surgery is not dead but has evolved.

Reconsidering vasectomy reversal over assisted reproduction in older couples.

OBJECTIVE: To provide pregnancy and live birth rates from a contemporary series of vasectomy reversals in men with female partners aged ≥35 years and to correlate the results with IVF. SETTING: Tertiary academic referral center. DESIGN: Retrospective comparative study of prospectively collected database. PATIENT(S): Two hundred forty-six men who underwent vasectomy reversal for fertility with female partner aged ≥35 years. INTERVENTION(S): Vasovasostomy or vasoepididymostomy. MAIN OUTCOME MEASURE(S): Correlation of pregnancy and live birth rate of this cohort by age groups with most recently published pregnancy and live birth rate per IVF cycle. RESULT(S): One hundred thirty-six men who underwent vasectomy reversal between 2006 and 2014 met our inclusion criteria. Overall pregnancy and live birth rates were 35% and 30%, respectively. Subgroup analysis by female age groups (35-37, 38-40, >40 years) demonstrated pregnancy and live birth rates comparable to those per IVF cycle by age groups according to a recently published (2015) national report. CONCLUSION(S): Vasectomy reversal should be strongly considered in men with a partner aged ≤40 years. Additionally, vasectomy reversal can be considered in carefully selected patients even with a partner aged >40 years.

Disease spectrum and treatment patterns in a local male infertility clinic.

OBJECTIVE: To review disease spectrum and treatment patterns in a local male infertility clinic. DESIGN: Case series. SETTING: Male infertility clinic in a teaching hospital in Hong Kong. PATIENTS: Patients who were seen as new cases in a local male infertility clinic between January 2008 and December 2012. INTERVENTION: Infertility assessment and counselling on treatment options. MAIN OUTCOME MEASURES: Disease spectrum and treatment patterns. RESULTS: A total of 387 new patients were assessed in the male infertility clinic. The mean age of the patients and their female partners was 37.2 and 32.1 years, respectively. The median duration of infertility was 3 years. Among the patients, 36.2% had azoospermia, 8.0% had congenital absence of vas deferens, and 48.3% of patients had other abnormalities in semen parameters. The commonest causes of male infertility were unknown (idiopathic), clinically significant varicoceles, congenital absence of vas deferens, mumps after puberty, and erectile or ejaculatory dysfunction. Overall, 66.1% of patients chose assisted reproductive treatment and 12.4% of patients preferred surgical correction of reversible male infertility conditions. Altogether 36.7% of patients required either surgical sperm retrieval or correction of male infertility conditions. CONCLUSIONS: The present study provided important local data on the disease spectrum and treatment patterns in a male infertility clinic. The incidences of azoospermia and congenital absence of vas deferens were much higher than those reported in the contemporary literature. A significant proportion of patients required either surgical sperm retrieval or correction of reversible male infertility conditions.

Analysis of international practice patterns regarding postvasectomy fertility options.

OBJECTIVE: To review the management of postvasectomy fertility options by urologists with vs without andrology fellowship and compare the features of practice in the USA vs UK. MATERIALS AND METHODS: We conducted an audit of all American Urological Association-affiliated urologists regarding their practice in managing men requesting vasectomy reversal (VR). Standards of practice were assessed against 10 index parameters deemed, by 1 UK study, to reflect best practice. Fisher exact test was used to test the hypothesis that management of postvasectomy fertility options and practice of VR are no different when undertaken by urologists with vs without andrology training and no different in the USA vs UK. RESULTS: Three hundred twenty-five of 645 US respondents (50.4%) practiced VR vs 178 of 213 (83.6%) in the UK; only 11.9% in the US and 10% in the UK performed >25 and >15 (P <.0001) VR/year, respectively. Compared with the UK urologists the US urologists offered more detailed information on all fertility options and/or outcomes, used microsurgical techniques more often, but less frequently counseled couples together, and referred patients to specialist centers for in vitro fertilization with intracytoplasmic sperm injection (P <.0001-.05). Only 74 of the US and 61 of the UK urologists were fellowship-trained in andrology. Most non-fellowship-trained urologists, in both the countries, performed <5 VR/year and were, statistically, significantly less likely to counsel couples about all fertility options, be conversant in in vitro fertilization with intracytoplasmic sperm injection, provide individualized outcomes data, and use microsurgical techniques (P <.0001-.05). CONCLUSION: Significant differences exist in the standards of practice between both the US and UK urologists performing VR. Concordance with the indices of "best practice" improves with andrology training and increasing number of procedures performed.

Vasectomy demographics and postvasectomy desire for future children: results from a contemporary national survey.

OBJECTIVE: To describe the longitudinal demographics and family planning attitudes of vasectomized men with the use of the National Survey for Family Growth (NSFG). DESIGN: Retrospective cohort analysis of the NSFG with the use of national projections and multivariable regressions. SETTING: In-home survey. PATIENT(S): The NSFG sampled 10,403 men aged 15-45 years from 2006 to 2010 regarding family planning attitudes. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Vasectomy and desire for children. RESULT(S): There were 3,646,339 (6.6%) vasectomized men aged 18-45 years in the U.S. On multivariable regression the following factors increased the odds of having a vasectomy: currently married (odds ratio [OR] 7.814), previously married (OR 5.865), and increased age (OR 1.122) and income (OR 1.003). The odds of having a vasectomy increased with number of children. The following factors decreased the odds of having a vasectomy: immigrant status (OR 0.186), African American (OR 0.226), Hispanic (OR 0.543), Catholic (OR 0.549), and other non-Protestant religion (OR 0.109). Surprisingly, an estimated 714,682 (19.6%) vasectomized men in the U.S. desire future children. Men practicing a religion (OR 8.575-15.843) were more likely than atheists to desire children after vasectomy. 71,886 (2.0%) vasectomized men reported having a vasectomy reversal. CONCLUSION(S): This study highlights the importance of preoperative counseling for permanency of vasectomy and reveals an opportunity to counsel couples about vasectomy versus tubal ligation.

[The influence of inguinal surgery on the success of a vasectomy reversal]. / Die Bedeutung inguinaler Operationen für die Refertilisierung bei vasektomierten Männern.

The retrospective study of 1327 vasectomized patients with the need for vasectomy reversal shows previous inguinal surgery in 5,9 %. In 1.7 % of the patients the vasectomy was done by an inguinal approach, causing the impossibility of the vasectomy reversal in 0,9 %. In 0,5 % the inguinal vasectomy was done accidentally during an inguinal hernia repair. The chances for successful vasectomy reversal are greatly reduced after inguinal vasectomy. The clinical and legal consequences of an inguinal vasectomy are discussed.

Pregnancy rate after vasectomy reversal in a contemporary series: influence of smoking, semen quality and post-surgical use of assisted reproductive techniques.

UNLABELLED: Study Type - Outcomes (cohort series). Level of Evidence 2b What's known on the subject? and What does the study add? Microsurgical vasectomy reversal is an effective and cost-effective method of reinstating fertility in a man who has previously had a vasectomy. The current literature indicates that the success rate (i.e. potency and pregnancy rates) are dependent primarily on the time elapsed since vasectomy and the age of the female partner. Using a multivariate Cox regression model, evaluation of the influence of preoperative data (including smoking) and semen parameters indicates a significant influence of post-surgical sperm motility only, on time to first pregnancy. The use of assisted reproductive techniques, when natural pregnancy failed, was successful in ≈50% of couples who attempted this procedure and accounted for an absolute increase in pregnancy rate of 14%. OBJECTIVE: • To determine the influence of smoking, postoperative semen characteristics and the use of an assisted reproductive technique (ART) on pregnancy rate in a contemporary series of men undergoing vasectomy reversal. PATIENTS AND METHODS: • Between January 2002 and January 2009, 186 vasectomy reversals were performed. Of the 171 patients who could be contacted for follow-up, 162 attempted pregnancy and constitute the study group. • Semen analysis was performed 3 months after the procedure and at subsequent 3-monthly intervals. • Patient characteristics and surgical information were obtained from a computerized database, and follow-up data were collected by telephone interview. • A multivariate Cox regression model was used to discern possible prognosticators with respect to pregnancy outcome. RESULTS: • The overall patency rate was 91.4%, with a natural pregnancy rate of 44.4% and a subsequent 14.2% of patients conceiving using a ARTs resulting in a total pregnancy rate of 58.6%. Multiple pregnancies were obtained by 20.4% of couples. • Smoking of the male or female partner did not influence the probability of conception. • In a multivariate model that included, among other factors, time since vasectomy, female age and semen characteristics, only sperm motility was significantly related to natural pregnancy outcome. • The probability of obtaining a natural pregnancy within 2 years after surgery is 53% for men with sperm motility >20% (WHO a+b) compared to 19% for men with sperm motility <5% (P= 0.003). CONCLUSIONS: • A clear and significant association between sperm motility and the probability of conception was found, whereas smoking, female age and time since vasectomy appeared to have no influence on pregnancy outcome in this patient cohort. • The use of ARTs accounted for an absolute increase in pregnancy rate of 14.2%.

Nomogram to preoperatively predict the probability of requiring epididymovasostomy during vasectomy reversal.

PURPOSE: Up to 6% of men who undergo vasectomy may later undergo vasectomy reversal. Most men require vasovasostomy but a smaller subset requires epididymovasostomy. Outcomes of epididymovasostomy depend highly on specialized training in microsurgery and, if predicted preoperatively, might warrant referral to a specialist in this field. We created a nomogram based on preoperative patient characteristics to better predict the need for epididymovasostomy. MATERIALS AND METHODS: We evaluated patients who underwent primary vasectomy reversal during a 5-year period. Preoperative and intraoperative patient data were collected in a prospectively maintained database. We evaluated the ability of age, years since vasectomy, vasectomy site, epididymal fullness and granuloma presence or absence to preoperatively predict the need for epididymovasostomy in a given patient. The step-down method was used to create a parsimonious model, on which a nomogram was created and assessed for predictive accuracy. RESULTS: Included in the study were 271 patients with a mean age of 42 years. Patient age was not positively associated with epididymovasostomy. Mean time from vasectomy to reversal was 9.7 years. Time to reversal and a sperm granuloma were selected as important predictors of epididymovasostomy in the final parsimonious model. The nomogram achieved a bias corrected concordance index of 0.74 and it was well calibrated. CONCLUSIONS: Epididymovasostomy can be preoperatively predicted based on years since vasectomy and a granuloma on physical examination. Urologists can use this nomogram to better inform patients of the potential need for epididymovasostomy and whether specialist referral is needed.

Effect of female partner age on pregnancy rates after vasectomy reversal.

OBJECTIVE: To determine the effect of female partner age on pregnancy rates after vasectomy reversal. DESIGN: Retrospective review. SETTING: Two academic infertility practices. PATIENT(S): Men undergoing vasectomy reversal and their partners. INTERVENTION(S): Microsurgical vasectomy reversal. MAIN OUTCOME MEASURE(S): Patency and pregnancy rates. RESULT(S): Two hundred ninety-four patients met the inclusion criteria. Groups were similar with regard to types of procedure performed (vasovasostomy or vasoepididymostomy), obstructive interval, female factors, number of repeat procedures, and quality of vasal fluid. Patency rates were 90%, 89%, 90%, 86%, and 83% for patients with female partners aged 20-24, 25-29, 30-34, 35-39, and 40+ years, respectively. Pregnancy rates were 67%, 52%, 57%, 54%, and 14% for patients with female partners aged 20-24, 25-29, 30-34, 35-39, and 40+ years, respectively. The pregnancy rate for couples with female partner aged 40 or older was lower than for those with the female partner aged 39 or younger (14% vs. 56%). CONCLUSION(S): Pregnancy rates for vasectomy reversal were good regardless of female age as long as the partner was 39 years old or younger. Pregnancy rates were lower if the female partner was 40 or more years old.

Multi-institutional validation of vasectomy reversal predictor.

PURPOSE: Some urologists who perform vasectomy reversals are not experienced with performing VE. A model to preoperatively identify patients who may require referral to an experienced VE surgeon was created (). We tested the model at multiple institutions. MATERIALS AND METHODS: The model had previously been designed in 483 patients who underwent vasectomy reversal at 1 institution (100% sensitive and 59% specific for predicting the need for VE). It was based on time since vasectomy and patient age. We tested it prospectively in 33 patients and retrospectively in a total of 312 at 6 other institutions. The predictive accuracy of the model was compared to using a simple duration from vasectomy cutoff alone, as is used in clinical practice. RESULTS: The model had 84% sensitivity and 58% specificity for detecting the need for VE in a total of 345 patients at 7 institutions. If using only a duration from vasectomy cutoff of 10 years to predict the need for VE, sensitivity was only 69%. At a cutoff of 4 years sensitivity was 99% but specificity was only 23%. Thus, the model performed better than any specific duration cutoff alone. CONCLUSIONS: The predictive model provides 84% sensitivity for detecting patients who may require VE during vasectomy reversal across 7 institutions (58% specificity). The model more accurately predicts the need for VE than using a specific duration from vasectomy cutoff alone.

Model to predict if a vasoepididymostomy will be required for vasectomy reversal.

PURPOSE: We devised a model to predict, preoperatively, the need for a vasoepididymostomy (VE) when performing a vasectomy reversal. Urologists could use it to identify those patients who need a referral to an experienced VE surgeon. MATERIALS AND METHODS: We performed a retrospective review of 483 patients who underwent vasectomy reversal by a single surgeon (AJT) including 393 vasovasostomies and 90 vasoepididymostomies. Selection was based on chart availability. Established criteria were used in deciding the type of reversal (eg gross appearance and microscopic examination of vasal fluid). Type of reversal, patient age and time since vasectomy were recorded. Univariate analysis revealed that patient age (p <0.001) and time since vasectomy (p <0.001) were significant predictors of reversal type. On multivariate logistic regression analysis, time since vasectomy (p <0.001) was the only significant independent predictor. We designed a linear regression algorithm based on time since vasectomy and patient age to predict if a VE would be performed. The model was designed using 433 patients and then tested on a separate randomly selected 50 patient group. The model was designed to be 100% sensitive in detecting patients requiring VE. RESULTS: In the test group the model was 100% sensitive in predicting VE with a specificity of 58.8%. The area under the ROC curves for the design and test groups was 0.8. Palm (PalmSource Inc., Sunnyvale, California) and Windows (Microsoft Corporation, Redmond, Washington) versions are available as free shareware from www.uroengineering.com. CONCLUSIONS: The model is 100% sensitivity in detecting those patients who may require a VE during vasectomy reversal (specificity of 58.8%). It may allow urologists to preoperatively identify these patients.

[Our experience with simplified vasovasostomy. Review of our results during the last 5 years]. / Nuestra experiencia en vasovasostomia simplificada. Revisión de los resultados obtenidos en los ultimos 5 años.

OBJECTIVES: We currently see an increase of demand of vasectomy reversion, mainly due to the wish of recovering fertility. METHODS: We review 21 cases of vasovasostomy performed at our department over the last 5 years with the single layer technique under optical magnification, comparing our results with those from bibliography for both vasovasostomy and in vitro fecundation techniques used in patients with obstructive azoospermia, specifically intracytoplasmic spermatozoids injection (ICSI). RESULTS: Success rates obtained for permeability, pregnancy, and births were 80%, 33%, and 26.66% respectively. CONCLUSIONS: Our results in terms of pregnancies are equivalent to those obtained by ICSI. These data, together with the disadvantage of greater rates of multiple pregnancies associated with in vitro fecundation techniques, moved us to choose vasovasostomy as the initial option for treatment of male infertility secondary to vasectomy.

[Vasectomy today: a review of 1,275 vasectomies in 10 years]. / Vasektomie heute. Eine Bestandserhebung nach 1275 Vasektomien in 10 Jahren.

We report on a large series of 1,275 patients who underwent outpatient vasectomy performed by a single urological surgeon within a 10-year period. In addition, the results of a prospective questionnaire-based study on 217 patients regarding their opinions and motivation, and the financial aspects of the vasectomy are discussed. The mean age was 37.0+/-5.9 years. A total of 98.4% of the patients had an uneventful postoperative course. The average duration of sick leave was 2.2+/-0.21 days. During the study period, the length of sick leave dropped significantly from 2.63 (1990/91) to 1.1 days (1998/99; P=0.001). Efficacy was documented with azoospermia rates of 96.6% and 98.5% in patients who presented for two and three sperm examinations, respectively. A vast majority of patients (94.6%) felt that the procedure should be covered by their health insurance, although 88.1% stated they would also pay by themselves. A minority of patients (0.7%: 9/1,275) subsequently considered vasectomy reversal. The wish to reverse the vasectomy was significantly associated with a younger patient age. In conclusion, outpatient vasectomy provides a safe and reliable form of contraception at low cost. Overall satisfaction in appropriately counselled patients is very high. Based on these findings, further attempts to propagate vasectomy as a timely form of contraception are medically and socioeconomically recommended.

Outcomes of vasectomy reversal performed for men with the same female partners.

OBJECTIVES: To review the fertility outcomes of patients who underwent vasectomy reversal and attempted conception with the same female partners. METHODS: A retrospective review of two surgeons' experience was performed. Patency was defined as the presence of motile sperm. Patients with less than 6 months of follow-up were excluded from the patency rate analysis unless they had sperm in the semen sample. Similarly, patients with less than 6 months of follow-up or no ongoing interest in establishing conception were excluded from the pregnancy rate analysis unless they had established a pregnancy. RESULTS: Of 200 consecutive men, 34 (17%) underwent microsurgical vasectomy reversal with the same female partner. All but two of the couples had previous proven fertility. The procedures performed for those who pursued fertility were bilateral vasovasostomy (n = 27), vasovasostomy/vasoepididymostomy (n = 4), and bilateral vasoepididymostomy (n = 1). The mean obstructive interval was 5 years (range 4 months to 10 years). The mean female partner age was 31.9 years (range 26 to 38). The median follow-up was 8 months (range 1 to 48). Patency was achieved in 27 (93%) of 29, and pregnancy occurred in 15 (60%) of 25 cases with sufficient follow-up. The ongoing or delivered rate was 56% (14 of 25). Female factor problems were present in three couples, and two miscarriages occurred for couples with known female factor problems. CONCLUSIONS: Microsurgical vasectomy reversal may have higher success rates when performed for couples with the same female partner. These results may be related to a shorter obstructive interval and a history of previous fertility as a couple.

Current practice in the management of vasectomy reversal and unobstructive azoospermia in Merseyside & North Wales: a questionnaire-based survey.

OBJECTIVE: To investigate the current incidence of vasectomy reversal procedures, the techniques used and which practitioners use them. PATIENTS AND METHODS: Using a questionnaire, 130 general surgeons and urologists practising in Merseyside and North Wales were surveyed. RESULTS: The response rate was 74%, with 24 urological surgeons and 14 general surgeons undertaking vasectomy reversal. Annually, urological surgeons carried out significantly more procedures than did general surgeons, at 8.5 and 5.3 (P = 0.029), respectively. They were also more likely to use double-layer closure and microsurgical techniques, whilst significantly less likely to use stents. Urologists reported significantly greater patency rates, at 76% and 52% (P = 0.017), respectively, with no significant differences in subsequent pregnancy rates (30% vs 25%). Only one practitioner checked tubal patency in the female partner before vasectomy reversal. CONCLUSIONS: The use of vasectomy reversal is a cost-effective treatment for men wanting paternity after vasectomy. The technique used by the clinician and proper audit of the results require close attention; it would also appear to be obvious that all the partners of men seeking a vasectomy reversal should have their fertility status established before reversal, something that is clearly not done at present.

The trends of vasectomy reversal in the forces.

A reversal of a vasectomy is required in about 3% of men who undergo vasectomy. We set out to examine the relationships between the age at which vasectomy was performed and the interval before subsequent reversal within the context of the armed forces. Thirty seven patients were identified from hospital records, as having undergone a reversal of vasectomy in the preceding two years, and thirty one sets of notes were available for inspection. Ages at vasectomy and at reversal were recorded and, where stated in the notes, if there had been a change in partner prior to the reversal request. Twelve (39%) men were under the age of thirty years at the time of their vasectomy, with a mean time to reversal of 4.4 years. Nineteen (61%) were over the age of thirty years at time of the vasectomy and their mean time to reversal was 7.2 years. Where recorded, the reason for requesting a reversal was a change in partner in 90% of men. Men who had their vasectomies before reaching the age of thirty were more likely to undergo reversal in a significantly shorter period of time when compared to those over thirty years. The disseminated criteria for vasectomy should be adhered to and appropriate preoperative counselling by surgeons may be useful.

Creatine kinase as an indicator of sperm quality and maturity in men with oligospermia.

OBJECTIVES: To determine the differences among the creatine kinase (CK) levels in the spermatozoa of subfertile men with mild, moderate, or severe oligospermia and to examine the differences in CK activity between infertile patients with various clinical diagnoses and a group of normal healthy donors (control). CK is a marker of sperm maturity that correlates with the sperm fertilizing capacity. Elevated levels are associated with an increased rate of functional abnormalities and increased cytoplasmic retention. METHODS: We compared the CK levels in 51 oligospermic men who could not initiate a pregnancy. Patients were categorized according to their degree of oligospermia as defined by the total sperm count: mild (greater than 10 to 40 x 10(6); n = 30), moderate (5 to 10 x 10(6); n = 11), and severe (less than 5 x 10(6); n = 10). These patients were further classified according to their diagnosis (ie, varicocele, n = 24; unexplained infertility, n = 17; vasectomy reversal, n = 9; and unknown diagnosis, n = 1). A separate group consisting of 25 healthy donors was included as a control group. A computer-assisted semen analyzer assessed the sperm characteristics, and the CK levels were measured using a CK test kit after the enzyme was extracted with Triton-X. RESULTS: The CK levels were significantly higher in the sperm of the severely oligospermic group (8.8 +/- 6.5 IU/10(8) sperm) than in the moderate (0.50 +/- 0.19 IU/10(8) sperm) and mild (0.49 +/- 0.15 IU/10(8) sperm) groups (P <0.0001). The mean CK level in the severely oligospermic group was 18-fold higher than that in the moderate (P = 0.03) and mild (P <0.001) groups. The CK levels were significantly higher in all three infertile groups compared with the donor group (0.06 +/- 0.01 IU/10(8) sperm). Patients with varicocele had the highest CK level (3.42 +/- 2.56 IU/10(8) sperm) compared with patients in the vasectomy reversal group (1.73 +/- 0.98 IU/10(8) sperm) and the idiopathic infertility group (0.26 +/- 0.08 IU/10(8) sperm). CONCLUSIONS: Elevated CK levels are associated with severe oligospermia, irrespective of the clinical diagnosis. CK may be a sensitive indicator of sperm quality and maturity in the follow-up of patients treated for male factor infertility.