Long-term pregnancy outcomes after deferential vessel‑sparing microsurgical vasoepididymostomy

Introduction

Epididymal obstruction is the most common cause of obstructive azoospermia (OA), accounting for 42.4–48% of cases. The treatment of epididymal obstruction has been a technical challenge (1). Microsurgical vasoepididymostomy (MVE) is often concerned as a cost-effective alternative to in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI), and it allows couples to have a chance of natural conception (1). In addition, microsurgical longitudinal intussusception vasoepididymostomy (LIVE) is the gold standard for achieving higher patency rates (2). Meta-analysis of the literature has reported a mean postoperative patency rate of 72% after MVE. However, the average pregnancy rate for MVE is only 31.1%, and the natural pregnancy rate is 21% (3,4). Low pregnancy rates after MVE are a critical factor affecting the treatment outcome for epididymal obstruction.

The causes of epididymal obstruction mainly include vasectomy, infection, idiopathic factors, congenital abnormalities and trauma. The majority of epididymal obstructions in western countries are caused by vasectomy, while in Asian countries, such as China, infection or idiopathic factors are more common causes of epididymal obstruction (5). The obstructive interval (OI) is thought to be an important prognostic factor in vasectomy reversal (VR) success. Longer OI are more likely to require vasoepididymostomy (VE). The studies demonstrated a 76% pregnancy rate for men with OI of ≤3 years while men with OI of >15 years had a 30% pregnancy rate (6). The OI in patients with epididymal obstruction in Asian countries, such as China, is often undetermined. Three months after VE surgery, sperm quality gradually improved, suggesting a gradual process of fertility recovery in patent patients after VE surgery (7). Previous VE studies have underestimated the natural pregnancy rate after VE because they had a short follow-up period.

The spermatic cord contains three arteries that provide blood supply to the testis, epididymis, and vas deferens. They are the testicular artery, which runs parallel to the ipsilateral deferential artery, and the external spermatic artery (8). These three arteries provide collateral circulation to each other, with the deferential artery acting as the predominant blood supply at the MVE anastomosis. However, the standard MVE technique involves ligating the deferential artery (5). Therefore, the potential benefits of preserving deferential vessels during MVE have been brought into focus. We have previously reported early postoperative follow-up results in a small sample of patients who underwent deferential vessels-sparing during MVE with a single-armed LIVE (SA-LIVE), with a patency rate of 83.1% (49/59) and a natural pregnancy rate of 49.0% (24/49) (9). Compared with typical MVE (67.0%), deferential vessel-sparing MVE achieved a higher overall mean patency rate (83.0%) (1). This study has expanded the sample size and performed long-term follow-up to evaluate the long-term pregnancy rate of deferential vessel-sparing SA-LIVE in patients with epididymal obstruction without a history of vasectomy. We present this article in accordance with the STROBE reporting checklist (available at https://tau.amegroups.com/article/view/10.21037/tau-2026-1-0055/rc).

Methods

Patients

A retrospective study was conducted on 197 male patients who underwent deferential vessel-sparing modified SA-LIVE at The First Affiliated Hospital of Sun Yat-sen University in Guangzhou, China, from December 2013 to December 2018. The mean age of the patients was 31.1 [standard deviation (SD): 5.5, range, 18–47] years. The research procedures complied with the guidelines outlined in the Declaration of Helsinki and its subsequent amendments. Informed consent was obtained from each patient. The present study protocol was reviewed and approved by the Independent Ethics Committee for Clinical Research and Animal Trials of The First Affiliated Hospital of Sun Yat-sen University (approval No. 2020408).

Azoospermic patients confirmed on at least two semen analyses 6 weeks apart were included. Patients were excluded if there were abnormalities in semen pH, volume, or fructose concentration. A standard work-up as described by (the 2008 American Society for Male Reproduction Guidelines for obstructive azoospermia) was performed, and patients were excluded if another cause of azoospermia was identified. Patients with a history of vasectomy on admission history-taking, or those whose partners had abnormal fertility evaluations (as defined by the 2008 American Society for Reproductive Medicine criteria for female infertility, including ovulatory dysfunction, tubal disease, and uterine cavity abnormalities) before surgery or during follow-up were excluded from the study.

Preparation

Based on the patient’s comprehensive history, physical examination, and ultrasound findings, a diagnosis of epididymal obstructive azoospermia was considered. MVE was performed using a Leica surgical microscope (Model M520 MC-1, Leica Microsystems Schweiz AG, Heerbrugg, Switzerland). The vessels were retained (Figure 1A), and a modified SA-LIVE suture technique was used (Figure 1B). All procedures were performed by the same microsurgical team.

Figure 1 Schematic diagram of the SA-LIVE technique for deferential vessel-sparing. (A) The blood supply of the vasoepididymostomy and the vessel-sparing part of the deferential artery. The sparing deferential artery is carefully isolated and separated from the vas deferens by 1–3 cm. (B) Suturing with a modified SA-LIVE technique. The schematic illustration was modified from our previous publication (9). SA-LIVE, single-armed longitudinal intussusception vasoepididymostomy.

Postoperative care and follow-up

Patients were instructed to abstain from sexual activity for at least four weeks after surgery. Semen analyses was performed at 6 and 12 weeks and then every 3 months thereafter until pregnancy. In our center, IVF/ICSI is recommended for couples with no sperm found by semen analysis 18 months after surgery. Patency was defined as the presence of sperm (>10,000 mL⁻¹) in the semen sample. Patients were followed up via telephone to inquire about their postoperative semen routine and pregnancy status. We mainly conducted postoperative follow-up telephone interviews with patients via communication devices and smartphones. In addition, any complications and adverse events were recorded at each follow-up visit. Patients who did not perform the requisite semen analyses were excluded from the analytical sample.

A total of 197 patients who underwent deferential vessel-sparing modified SA-LIVE were enrolled in this study, among whom 176 patients (89.3%, 176/197) completed at least 18 months of follow-up in accordance with the study protocol.

Pregnancy and delivery outcomes were followed up in 141 patients with postoperative patency and their partners. Of these, 121 patients (85.8%, 121/141) received follow-up for at least 12 months after patency. The 20 patients who did not complete follow-up included: 9 unreachable patients; 3 patients whose spouses were diagnosed with infertility during pregnancy preparation; 1 patient using contraception for health reasons; 1 divorced patient; 1 unmarried patient; and 5 patients with late failure.

Two centralized telephone follow-ups were conducted in April 2019 and June 2021 for the 58 patients who did not achieve pregnancy within 12 months after patency. Among them, 51 patients (87.9%, 51/58) completed both follow-ups. Three patients were lost to follow-up in April 2019 and 4 patients in June 2021 as they were unreachable.

Statistical analysis

A Chi-squared test or Student’s t-test was performed for univariable analysis, and logistic regression was used for multivariable analysis to analyze the relationship between patency rate, natural pregnancy rate, and clinical characteristics (female age, etiology of epididymal obstruction, bilateral or unilateral anastomosis, presence of motile spermatozoa in epididymal fluid, and varicocele, etc.).

Our article published in 2018 covered patients who underwent deferential vessels-sparing SA-LIVE from December 2013 to December 2015, with a mean follow-up of 15.6 months (3 to 33 months) from the date of surgery, and reported a natural pregnancy rate of only 49.0% (24/49). That result did not account for patent patients lost to follow-up during the study. Moreover, among the 24 patients who achieved natural pregnancy, only one had a follow-up period extending 12 months after regaining patency. In contrast, the present study includes patients who underwent deferential vessels-sparing SA-LIVE from December 2013 to December 2018, these patients had an average follow-up period of 56 months (30 to 90 months) from the date of surgery, showing a significantly higher long-term natural pregnancy rate of 72.8%. To explain the difference in follow-up outcomes, we divided the patent patients into two groups for comparison: Group A (patients from December 2013 to December 2015) and Group B (patients from January 2016 to December 2018). Pregnancy rate was estimated by the Kaplan-Meier method and differences were determined by the log rank test. The data was analyzed using SPSS version 22.0 (IBM Corporation, Armonk, NY, USA). Statistical significance was considered if two-tailed P<0.05.

Results

In this study, 197 patients were treated with deferential vessel-sparing modified SA-LIVE, and 176 patients (89.3%, 176/197) completed at least 18 months of follow-up as defined in the study protocol. Preoperative and intraoperative characteristics are demonstrated in Table 1. The average operative time for unilateral deferential vessel-sparing modified SA-LIVE anastomosis was 127.6 minutes. The mean follicle-stimulating hormone (FSH) of the patients was 4.0 (SD: 2.6) mIU mL⁻¹, and the mean luteinizing hormone (LH) was 4.0 (SD: 2.0) IU L⁻¹.

Patency was defined as the presence of sperm (>10,000 mL⁻¹) in the semen sample. A patency rate of 80.1% (141/176) was achieved, the mean time to achieve patency is 4.5 months (range, 1–12 months), and we observed “late failure” in 3.0% (5/176) of patients. The mean sperm concentration was 22.8×10⁶ (range, 1.0×10⁶–97.9×10⁶) mL⁻¹, and the mean sperm motility rate was 26% (range, 0–80%). Univariate analysis revealed that bilateral or unilateral anastomosis were associated with postoperative patency (Table 2). However, clinical characteristics which affected the postoperative patency rate were not found on multivariate analysis (Table 2). There were no reports of serious adverse effects or procedural complications of deferential vessel-sparing modified SA-LIVE.

The average follow-up of 141 patent patients and their partners was 56 months (range, 30–90 months) to determine pregnancy and birth rates, and a complete long-term follow-up of 114 patent patients (80.9%, 114/141) was conducted. Of these 114 patients with long-term follow-up data available, 72.8% (83/114) achieved pregnancy through natural conception. Among the 27 patent patients who lost follow-up, 20 patients were lost to follow-up within 1 year after the reversal, and 7 patients were lost after 1 year. As the follow-up time extended, the rate for loss of follow-up also increased. The 27 patients lost to follow-up included: 16 patients were lost to follow-up because we could not reach them, three patients’ spouses were found to be infertile during pregnancy preparation, one patient used contraception for health reasons, one patient divorced, one patient was unmarried, and five patients experienced “late failure”.

The overall pregnancy rate in the 114 patent patients was 84.2% (96/114), and the natural pregnancy rate was 72.8% (83/114). Two couples who conceived naturally reported miscarriage after pregnancy. The natural pregnancy time range from 1 to 48 months from the date of surgery, and the average time is 12.5 months. The average time from regaining patency (from the first semen analysis showed that sperm >10,000 mL⁻¹) to natural conception was 8.5 months (range, 0 to 37 months, Figure 2). In this study, the 121 patients who were followed up for more than 1 year after regaining patency, the natural pregnancy rate within 1 year was 52.1% (63/121), among the 51 patients who did not conceive naturally within 1 year after the reversal, their natural pregnancy rate in the following 3 years was 39.2% (20/51). Of the 114 patients, 8 had concomitant closed scrotal trauma. Pregnancy-related analysis was not performed because the specific injury conditions varied. Forty-nine of the 114 patients had concomitant infections, including 42 cases of unilateral epididymitis, 6 cases of bilateral epididymitis, and 1 case of gonorrhea. Regarding the duration of infection: 23 cases were ≤3 years and 26 cases were >3 years. Neither a history of infection nor the interval between the date of infection and the date of surgery was associated with the postoperative pregnancy rate (Table 3). Univariate analysis revealed that left spermatic varicoceles were associated with natural pregnancy (Table 3). However, on multivariate analysis, female age and left spermatic varicoceles were independent predictors of natural pregnancy (Table 3). Factors including older spouse age (≥35 years) and combined left spermatic varicoceles may be related with lower natural pregnancy rates.

Figure 2 Kaplan-Meier plot of cumulative natural pregnancy rate by after regaining patency time (after spermatozoa >10,000 mL⁻¹). Pregnancy was 75.7% versus 71.4% of patent patients with Group A versus Group B (Group A: patients from December 2013 to December 2015; Group B: patients from January 2016 to December 2018). The result suggests no significant difference between the two groups (P=0.55).

Of these 114 patent patients with long-term follow-up data available, we divided the patients into two groups for comparison: Group A (patients from December 2013 to December 2015) and Group B (patients from January 2016 to December 2018). There were no significant differences between the two groups in terms of female age, incidence of left varicocele, time to regaining patency, or waiting time for natural pregnancy (Table 4). The cumulative natural pregnancy rates over time for both Group A and Group B were similar, which were 75.7% (28/37) and 71.4% (55/77) respectively, with the natural pregnancy rate increasing over time and peaking at 2–3 years after regaining patency (Figure 2). The low pregnancy rates reported in our 2018 article were due to the lack of accounting for patients lost to follow-up and the shorter duration of follow-up.

The mean time to IVF/ICSI conception was 21.3 months (range, 8–34 months) after regaining patency. The average number of IVF/ICSI clinical pregnancy cycles was 1.3 (range, 1–2), and the clinical pregnancy rate (CPR) per IVF/ICSI cycle was 76.5% (13/17). Among couples undergoing IVF/ICSI, 92.3% (12/13) were able to use freshly ejaculated sperm, and one patient had sperm obtained by testicular puncture due to the demise of newly ejaculated sperm.

Discussion

To our knowledge, this study represents the first long-term follow-up investigation of patency and pregnancy outcomes following deferential vessel-sparing SA-LIVE in patients with epididymal obstruction without prior vasectomy.

In this study, we reported that the patency rate of deferential vessel sparing modified SA-LIVE was as high as 80.1%. The most recent literature indicates that deferential vessel-sparing MVE achieves a higher overall mean patency rate (83.0%) compared with conventional MVE (67.0%) (1). It has been well reported that non-anastomotic biliary stricture is closely related to injury and repair of the peribiliary vascular plexus (10). Therefore, deferential vessel sparing in MVE may contribute to improve the postoperative patency rate. We hypothesized that deferential vessel-sparing in MVE improve the vascular blood supply to the anastomosis, thereby reducing ischemic-related fibrosis and scar formation. The low rates of late failure in our cohort further supports this hypothesis, as late failures typically result from ischemia-related, time-dependent changes.

In our initial experience, deferential vessel-sparing was technically feasible, and well-trained microsurgeons were already equipped with the skill set to isolate the deferential vessels safely (9). Deferential vessel-sparing might require additional operative time and technical challenges. However, it might be worth it if higher patency and pregnancy rates were reproducible, as the benefit to patients would certainly outweigh the demands of a more meticulous dissection and surgical approach.

Although the microsurgical technique and surgeon expertise are the most critical factors for the success of MVE, other factors may also influence postoperative patency rates. Some factors, such as the unilateral or bilateral anastomosis, etiology of epididymal obstruction, and the discovery of motile sperm at the anastomotic site, have been reported to be associated with postoperative patency rates (3,7). However, the present study did not find that these clinical characteristics significantly affected postoperative patency rate (Table 2).

Tension-free anastomosis is essential for successful MVE patency, which may be readily performed without ligating the deferential vessels on the level of epididymal corpus or epididymal caudal (Figure 1). However, when the anastomosis is performed at the caput of the epididymis, it may be necessary to mobilize the distal vas deferens more extensively in order to ensure an excellent tension-free anastomosis. The distal vas deferens can be freed to the height of the inguinal canal, and caution should be exercised to ensure its integrity during the procedure.

Although the rate of “late failure” using the LIVE technique has previously been reported to be lower than non-LIVE (11), the incidence of “late failure” in patients with deferential vessel-sparing modified SA-LIVE in this study was 3.0% at 18 months postoperatively. Therefore, surgical reconstruction can be considered again for these patients with “late failure”, because MVE remains effective in the treatment of patients with previous surgical failure (11). In addition, assisted reproductive technology (ART) is also recommended as the next treatment option for patients with “late failure”.

In the present study, the average follow-up period for the 114 patent patients with deferential vessel-sparing modified SA-LIVE was 56 months (30 to 90 months), with a high natural pregnancy rate of 72.8%. Previous studies have shown that the VE rate of VR increased linearly at a rate of 3% per year for 1–22 years after vasectomy, but stabilized at 72% at 24–38 years. Additionally, the sperm counts remain unchanged with the prolongation of time after vasectomy, but the motile sperm counts decreased significantly. With longer vasectomy intervals time, the partner might be older (12). These factors might be responsible for the low pregnancy rate in epididymal obstruction secondary to vasectomy. The results of this study suggest that epididymal obstructions not secondary to vasectomy are associated with a higher postoperative pregnancy rate, although OI cannot be determined. Deferential vessel-sparing SA-LIVE might improve natural pregnancy rate at a very early stage (13). The high pregnancy rate shown in our study does not exclude the positive effect of preserving vasal vessel. When patients with acquired obstructive azoospermia underwent ICSI, the clinical pregnancy rate (CPR) per cycle was approximately 45% (14). In this study, 13 couples with patent patients successfully conceived by IVF/ICSI, and the CPR of IVF/ICSI was as high as 76.5%, which was significantly higher than that of untreated acquired obstructive azoospermia.

Previous meta-analyses have shown that the average natural pregnancy rate after MVE is only 21–40.5% (3,4), with most studies not detailing the average time to natural pregnancy (15), and some report an average pregnancy time of 6.9 to 9.9 months post-surgery (3). In this study, the average time to pregnancy from the date of surgery was calculated to be 12.5 months (SD: 10.0 months), which is longer because our long-term follow-up included more patients who achieved natural pregnancy later. This effectively explains the higher natural pregnancy rates reported in our study.

We also found that the sperm quality of most patients gradually improved after regaining patency in this study. For patients who did not conceive within 1 year after regaining patency, approximately 39.2% (20/51) of couples with patent after VE could conceive naturally within 1 to 3 years after patency (Figures 2,3). According to the World Health Organization (WHO), infertility is a failure to conceive after 1 year or more of regular sexual intercourse without protective measures. Couples who have tried unsuccessfully to conceive naturally for 1 year require further clinical evaluation (16). The pregnancy rate for ART after MVE was reported as 32.9% in a previous study (4). The present study found that the current clinical recommendation for IVF/ICSI was also 1 to 3 years after patency for couples who had patency after VE but do not conceive naturally (Figure 3). Therefore, approximately 39.2% of couples with patients who could conceive naturally would be recommended for IVF/ICSI. Previous VE studies have underestimated the natural pregnancy rate after VE because of the short follow-up period and the premature recommendation of IVF/ICSI for couples with patency. Some studies have shown that children born through ART have higher birth defects and childhood cancers (17). Evidence-based medicine shows that the per-cycle CPRs of patients with acquired and congenital obstructive azoospermia in the ICSI treatment group are approximately 45.0% and 36.8%, respectively. However, ICSI treatment exposes female partners to potential procedural complications, such as ovarian hyperstimulation syndrome. Previous studies have reported that MVE can achieve relatively high pregnancy and patency rates. MVE has multifaceted significance in the treatment of male infertility. It enables natural conception, avoids complications that female partners may suffer from the ICSI protocol, and if patency is achieved but pregnancy does not occur, it can reduce the level of ART required (from ICSI to IVF). Furthermore, compared with ICSI, microsurgical reconstruction is a more cost-effective approach (14). Indications for IVF treatment in females include ovulatory dysfunction with unsuccessful pregnancy after pharmacological therapy, females aged <35 years with severe tubal disease (Hull and Rutherford grade III), females aged ≥35 years with any type of tubal disease or bilateral salpingectomy (16). Moreover, as long as the spouse or sexual partner allows, we believe it might be better to wait 2 to 3 years after VE patency before doing IVF/ICSI.

Figure 3 Kaplan-Meier plot of cumulative pregnancy rate by after regaining patency time of pregnant patients after more than 1-year post-patency. Pregnancy time after regaining patency was 21.2 (SD: 7.6) months in natural pregnancy group versus 21.3 (SD: 7.1) months in ART pregnancy group. The result suggests no significant difference between the two groups (P=0.71). ART, assisted reproductive technology; SD, standard deviation.

The underlying mechanism between epididymal obstruction and infection has not been clearly elucidated (18). Among the 114 patients included in the pregnancy rate analysis in this study, 49 had concomitant infections, including 42 cases of unilateral epididymitis, 6 cases of bilateral epididymitis, and 1 case of gonorrhea. Most patients with epididymal obstruction have a previous history of epididymitis or scrotal trauma, and long-term semen analysis is not routinely performed in such patients after epididymitis or scrotal trauma. Therefore, the exact time of epididymal obstruction caused by infection or trauma is often difficult to determine. In this study, the interval from infection to surgery was not associated with the postoperative pregnancy rate (Table 3), which may be attributed to the inconsistency between the date of infection and the onset of obstruction.

The prevalence of varicocele is 15% to 20% in the general population, 19% to 41% in patients with primary infertility, and over 80% in patients with secondary infertility (19). In this study, 35.1% of the 114 patent patients had combined varicocele, the postoperative natural pregnancy rate was found to be significantly associated with combined left varicocele (P<0.05; Table 3), with only 33.3% (7/21) of patent patients with combined left varicocele having a postoperative natural pregnancy rate after VE compared with 81.1% (60/74) of couples without varicocele. This study is the first to report that varicocele affects the postoperative pregnancy rate in VE. Varicocelectomy improves pregnancy rates in men with low fertility couples (20). Varicocele treatment should also be considered in men who have failed IVF/ICSI treatment, which may reduce deoxyribonucleic acid (DNA) fragmentation and improve IVF/ICSI outcomes and live birth rates (21). Goldstein reported a significantly higher rate of varicocele recurrence and testicular atrophy in 19 patients who underwent vasovasostomy (VV) and varicocelectomy (22). Patients with obstructive azoospermia undergoing reconstructive surgery generally do not undergo concomitant varicocele repair (23).

Zhang et al. reported a patient with epididymal obstruction who had undergone varicocelectomy and performed deferential vessel sparing MVE to preserve blood flow to the testes and avoid testicular atrophy (24). Our study validated the safety of a large sample of the deferential vessel-sparing modified SA-LIVE. However, there are no clinical studies of VE and varicocelectomy for varicocele in patients with OA. The chronology of the two procedures and their effect on pregnancy rates are unknown.

The age of the patient’s spouse was considered the most critical factor affecting conception, and the conception rate decreased significantly when the spouse was older than 35 or 40 years (25). In the present study, only 44.5% (4/9) of female age ≥35 years having a postoperative natural pregnancy rate after VE compared with 75.2% (79/105) of female age <35 years (Table 3). The success rate of IVF/ICSI tends to decrease when the woman is older than 35 years (26), whereas the pregnancy rate for surgical reconstruction of OA in women ≥35 years of age is similar to that of single-cycle IVF/ICSI. There is a paucity of high-quality evidence to guide patients toward IVF or surgical reconstruction, particularly in the older maternal age group. Surgical reconstruction is a cost-effective, reasonable option for couples with older maternal ages and less financial flexibility (27). The literature has reported that caudal or corpus anastomosis of the epididymis has a higher postoperative pregnancy rate than caput anastomosis during VE (7,28). In this study, 98.9% of patients were anastomosed at the caudal or corpus level of the epididymis, so it is difficult to evaluate the effect of anastomosis sites on postoperative pregnancy rates.

Our initial experience with deferential vessel-sparing SA-LIVE indicates that this modified microsurgical technique achieves favorable patency and pregnancy rates. This study has limitations. It is a single-center retrospective review, from a high-volume male infertility center with extensive experience in microsurgical techniques, which may limit the generalizability of deferential vessels-sparing MVE. Long-term follow-up was challenging in nearly 30% of our patients, though the data available is robust in that it provides much more clinically relevant metrics of patient pregnancy rates. Confounding variables, such as varicoceles, also make some of the results more challenging to interpret, though at the same time it is a more representative sample of the general population clinicians may encounter. However, a multicenter prospective randomized controlled clinical trial with a statistically sound clinical design and a large sample size is currently underway to further investigate the efficacy of deferential vessel sparing in MVE.

Conclusions

The epididymal obstructions that are not secondary to vasectomy are associated with a higher postoperative pregnancy rate, although OI cannot be determined. In this study, the cumulative natural pregnancy rates over time after surgery were similar between Group A (early enrollment) and Group B (late enrollment), indicating that the long-term pregnancy rate of deferential vessel-sparing SA-LIVE was stable and reproducible. Past VE studies have underestimated the natural pregnancy rate after VE because of the short follow-up period and the premature recommendation of IVF/ICSI for couples with patency. Moreover, as long as the spouse’s condition permits, we believe it may be more appropriate to wait 2 to 3 years after VE patency before performing IVF/ICSI.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://tau.amegroups.com/article/view/10.21037/tau-2026-1-0055/rc

Data Sharing Statement: Available at https://tau.amegroups.com/article/view/10.21037/tau-2026-1-0055/dss

Peer Review File: Available at https://tau.amegroups.com/article/view/10.21037/tau-2026-1-0055/prf

Funding: This research was supported by the Sun Yat-Sen University Clinical Research 5010 Program (No. 2022006), China National Health Commission Key Laboratory of Male Reproduction and Genetics Open Project (No. KF202001), Guangdong Basic and Applied Basic Research Foundation (Nos. 2021A1515110986 and 2024A1515010492), and Clinical Research Training Program, the East Division of The First Affiliated Hospital of Sun Yat-sen University (Nos. 2019002 and 2019008).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tau.amegroups.com/article/view/10.21037/tau-2026-1-0055/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The research procedures complied with the guidelines outlined in the Declaration of Helsinki and its subsequent amendments. Informed consent was obtained from each patient. The present study protocol was reviewed and approved by the Independent Ethics Committee for Clinical Research and Animal Trials of The First Affiliated Hospital of Sun Yat-sen University (approval No. 2020408).

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Zhu J, Yang Y, Zhu S, et al. Treatment Efficacy of Microsurgical Vasoepididymostomy for Obstructive Azoospermia: An Updated Systematic Review and Meta-Analysis. Andrology 2026;14:651-60. [Crossref] [PubMed]
2. Tang SX, Xiao H, Chen Q, et al. Factors affecting patency time and semen quality in a single-armed microsurgical vasoepididymostomy. Asian J Androl 2024;26:640-4. [Crossref] [PubMed]
3. Yoon YE, Lee HH, Park SY, et al. The role of vasoepididymostomy for treatment of obstructive azoospermia in the era of in vitro fertilization: a systematic review and meta-analysis. Asian J Androl 2019;21:67-73. [Crossref] [PubMed]
4. Wang Z, Wang X, Song C, et al. The pregnancy outcomes in patients with epididymal obstructive azoospermia after microsurgical vasoepididymostomy: a systematic review and meta-analysis. Front Med (Lausanne) 2023;10:1186729. [Crossref] [PubMed]
5. Chan PT. The evolution and refinement of vasoepididymostomy techniques. Asian J Androl 2013;15:49-55. [Crossref] [PubMed]
6. Fantus RJ, Halpern JA. Vasovasostomy and vasoepididymostomy: indications, operative technique, and outcomes. Fertil Steril 2021;115:1384-92. [Crossref] [PubMed]
7. Peng J, Zhang Z, Yuan Y, et al. Pregnancy and live birth rates after microsurgical vasoepididymostomy for azoospermic patients with epididymal obstruction. Hum Reprod 2017;32:284-9. [Crossref] [PubMed]
8. Lotti F, Maggi M. Ultrasound of the male genital tract in relation to male reproductive health. Hum Reprod Update 2015;21:56-83. [Crossref] [PubMed]
9. Lyu KL, Zhuang JT, Li PS, et al. A novel experience of deferential vessel-sparing microsurgical vasoepididymostomy. Asian J Androl 2018;20:576-80. [Crossref] [PubMed]
10. op den Dries S, Westerkamp AC, Karimian N, et al. Injury to peribiliary glands and vascular plexus before liver transplantation predicts formation of non-anastomotic biliary strictures. J Hepatol 2014;60:1172-9.
11. Farber NJ, Flannigan R, Li P, et al. The Kinetics of Sperm Return and Late Failure Following Vasovasostomy or Vasoepididymostomy: A Systematic Review. J Urol 2019;201:241-50. [Crossref] [PubMed]
12. Namekawa T, Imamoto T, Kato M, et al. Vasovasostomy and vasoepididymostomy: Review of the procedures, outcomes, and predictors of patency and pregnancy over the last decade. Reprod Med Biol 2018;17:343-55. [Crossref] [PubMed]
13. Li P, Liu N, Zhi E, et al. Vasal vessel-sparing microsurgical single-armed vasoepididymostomy to epididymal obstructive azoospermia: A retrospective control study. Andrologia 2021;53:e14133. [Crossref] [PubMed]
14. Zhang Z, Zhang Y, Zhang N. Clinical outcome of microsurgical vasoepididymostomy versus epididymal or testicular sperm retrieval combined with intracytoplasmic sperm injection in obstructive azoospermia males. Andrologia 2022;54:e14458. [Crossref] [PubMed]
15. Wan B, Wu Y, Wu Z, et al. Current progress on the curative effects of vasoepididymostomy for patients with obstructive azoospermia: An updated systematic review and meta-analysis of human studies. Andrology 2023;11:103-11. [Crossref] [PubMed]
16. World Health Organisation Guideline Development Group for Infertility. Recommendations from the WHO guideline for the prevention, diagnosis, and treatment of infertility†. Hum Reprod 2026;41:25-38.
17. Luke B, Brown MB, Wantman E, et al. The risks of birth defects and childhood cancer with conception by assisted reproductive technology. Hum Reprod 2022;37:2672-89. [Crossref] [PubMed]
18. Han H, Liu S, Zhou XG, et al. Aetiology of obstructive azoospermia in Chinese infertility patients. Andrologia 2016;48:761-4. [Crossref] [PubMed]
19. Dong L, Xin J, Zhang J, et al. Progress of the pathogenesis in varicocele: a narrative review. Can J Urol 2026;33:63-74. [Crossref] [PubMed]
20. Barone B, Amicuzi U, Tammaro S, et al. Male Infertility: A Comprehensive Review of Urological Causes and Contemporary Management. J Clin Med 2026;15:397. [Crossref] [PubMed]
21. Palani A, Cannarella R, Saleh R, et al. Impact of Varicocele Repair on Assisted Reproductive Technique Outcomes in Infertile Men: A Systematic Review and Meta-Analysis. World J Mens Health 2025;43:344-58. [Crossref] [PubMed]
22. Goldstein M. Surgical management of male infertility. In: Wein A, Kavoussi LR, Novick AC, et al, editors. Campbell-Walsh Urology. Philadelphia, PA: Elsevier Saunders; 2012:648-87.
23. Male Infertility Best Practice Policy Committee of the American Urological Association. Report on varicocele and infertility. Fertil Steril 2004;82:S142-S145.
24. Zhang Y, Wu X, Yang XJ, et al. Vasal vessels preserving microsurgical vasoepididymostomy in cases of previous varicocelectomy: a case report and literature review. Asian J Androl 2016;18:154-6. [Crossref] [PubMed]
25. Marti-Garcia D, Martinez-Martinez A, Sanz FJ, et al. Age-related uterine changes and its association with poor reproductive outcomes: a systematic review and meta-analysis. Reprod Biol Endocrinol 2024;22:152. [Crossref] [PubMed]
26. Vitagliano A, Paffoni A, Viganò P. Does maternal age affect assisted reproduction technology success rates after euploid embryo transfer? A systematic review and meta-analysis. Fertil Steril 2023;120:251-65.
27. Dubin JM, White J, Ory J, et al. Vasectomy reversal vs. sperm retrieval with in vitro fertilization: a contemporary, comparative analysis. Fertil Steril 2021;115:1377-83.
28. Shiraishi K, Matsuyama H. Outcomes of partial intussusception and endo-to-side vasoepididymostomy in men with epididymal obstructive azoospermia. Int J Urol 2020;27:1124-9. [Crossref] [PubMed]