Abstract
Objectives
Percutaneous epididymal sperm aspiration (PESA) is a minimally invasive surgical sperm retrieval technique used in patients unable to provide ejaculated spermatozoa. This study aimed to evaluate fertilization, clinical pregnancy, and live birth outcomes following intracytoplasmic sperm injection (ICSI) using epididymal sperm obtained via PESA over an 11-year period at a single tertiary referral center.
Methods
This retrospective cohort study analyzed 63 PESA–ICSI cycles performed in 46 male patients between January 2015 and December 2025. Indications for PESA included obstructive azoospermia (n=13 cycles) and medically refractory ejaculatory dysfunction (n=50 cycles). Outcomes were evaluated both at the cycle level and independently per embryo transfer (ET) procedure. Comparative analyses were performed according to PESA indication, embryo developmental stage at transfer, and transfer type.
Results
Sperm retrieval was completely successful in all 63 cycles (100%). Of 498 mature (MII) oocytes injected, normal fertilization (2PN) was achieved in 268, yielding an oocyte-level fertilization rate of 53.8%. Total fertilization failure occurred in only one cycle (1.6%). Embryo transfer was performed in 57 cycles, resulting in 68 individual transfer procedures (42 fresh and 26 frozen–thawed). The overall clinical pregnancy rate was 39.7% (25/63) per initiated cycle and 36.8% (25/68) per ET procedure. The overall live birth rate was 33.3% (21/63) per initiated cycle and 30.9% (21/68) per ET procedure. No statistically significant differences were observed between cleavage-stage and blastocyst-stage transfers with respect to clinical pregnancy (p=0.615) or live birth outcomes (p=1.000). No major procedural complications were recorded.
Conclusion
PESA combined with ICSI provides favorable reproductive outcomes with a low rate of total fertilization failure. These results were achieved despite a cohort characterized by diminished ovarian reserve and diverse male infertility etiologies. The high sperm retrieval success rate and consistent clinical outcomes support PESA as a reliable and effective sperm retrieval technique in contemporary assisted reproductive practice.
Keywords: Assisted reproductive techniques, Ejaculatory dysfunction, Intracytoplasmic sperm injection, Live birth, Male infertility, Percutaneous epididymal sperm aspiration
Surgical sperm retrieval techniques play a central role in the management of male infertility in patients who are unable to provide ejaculated spermatozoa. These techniques are commonly used in conditions such as obstructive azoospermia, ejaculatory dysfunction, anejaculation, retrograde ejaculation, and selected cases of severe erectile dysfunction. The introduction of intracytoplasmic sperm injection (ICSI) has revolutionized the treatment of these patients by enabling successful fertilization using surgically retrieved spermatozoa, thereby significantly expanding their reproductive potential.[1,2]
Among the available surgical sperm retrieval methods, percutaneous epididymal sperm aspiration (PESA) is widely recognized because of its minimally invasive nature, technical simplicity, and high sperm retrieval success rates.[3,4] PESA allows direct aspiration of spermatozoa from the epididymis and enables the use of mature sperm cells for ICSI. Clinical studies have reported favorable reproductive outcomes following PESA–ICSI in appropriately selected patients.[3,4] Epididymal sperm retrieval is also recognized as an established surgical option for ICSI.[5]
Numerous studies have reported favorable reproductive outcomes following PESA–ICSI, with live birth rates of approximately 30% per treatment cycle in contemporary cohorts.[3,6] Similarly, comparative clinical studies have shown that the origin of surgically retrieved spermatozoa does not significantly affect reproductive outcomes in ICSI cycles.[1,6] These findings support the clinical utility of PESA.
Importantly, the indications for PESA extend beyond classical obstructive azoospermia. Fang et al.[7] reported favorable fertilization and pregnancy outcomes following PESA–ICSI in patients with ejaculatory dysfunction, supporting the use of this technique in a broader range of clinical scenarios. Similar favorable reproductive outcomes have also been reported in other PESA–ICSI cohorts across different clinical settings and patient populations.[7,8] Furthermore, surgical sperm retrieval combined with ICSI has been associated with consistent reproductive outcomes in contemporary clinical cohorts.[8]
Despite these encouraging findings, variability in reported outcomes persists. This variability may reflect differences in patient populations, infertility etiology, surgical expertise, and laboratory protocols. In addition, long-term single-center outcome data remain limited, particularly in cohorts undergoing repeated PESA procedures and multiple embryo transfer attempts. Such data are essential for accurately evaluating real-world clinical effectiveness and cumulative reproductive outcomes.
Therefore, the aim of this study was to evaluate fertilization, embryological development, clinical pregnancy, and live birth outcomes following ICSI using epididymal sperm obtained by percutaneous aspiration over an 11-year period at a single tertiary referral center. By analyzing a well-characterized cohort treated under consistent clinical, laboratory, and surgical conditions, this study provides important insight into the clinical efficacy of PESA–ICSI in contemporary assisted reproductive practice.
Methods
Study Design and Setting
This retrospective cohort study was conducted at a tertiary university hospital. We reviewed all infertile couples who underwent IVF/ICSI treatment between January 2015 and December 2025 and identified cycles in which epididymal spermatozoa were obtained by percutaneous epididymal sperm aspiration (PESA) and used for ICSI. Male patients undergoing PESA because of an absolute inability to obtain ejaculated spermatozoa were included.
Obstructive azoospermia was clinically diagnosed based on confirmed repeated azoospermia, normal serum reproductive hormone profiles, bilaterally normal-sized testes, and the absence of physical examination or clinical findings suggestive of impaired spermatogenesis. Indications comprised obstructive azoospermia and severe ejaculatory dysfunction, including anejaculation, retrograde ejaculation, and severe erectile dysfunction refractory to maximum pharmacological therapy with phosphodiesterase-5 inhibitors, for which noninvasive collection methods or electroejaculation were either unsuccessful, contraindicated, or declined by the couple.
Each PESA–ICSI cycle was analyzed independently as a separate observational unit. This retrospective study used anonymized clinical data collected during routine clinical care. The study protocol was formally approved by the Baskent University Institutional Review Board (Project No: KA26/204; approval date: April 21, 2026) and was conducted in accordance with the Declaration of Helsinki. The study was supported by the Baskent University Research Fund.
PESA Procedure and Sample Processing
PESA was performed under local anesthesia using a 21-gauge butterfly needle attached to a syringe preloaded with a small volume of HEPES-buffered sperm preparation medium. All procedures were performed by a single experienced urologist specializing in male infertility and surgical sperm retrieval. Following aspiration, the epididymal fluid was immediately transferred into HEPES-buffered culture medium supplemented with human serum albumin and examined under an inverted microscope by experienced embryologists to confirm the presence of spermatozoa. Samples containing spermatozoa were concentrated by centrifugation and subsequently prepared either for immediate fresh use on the day of oocyte retrieval or for cryopreservation for subsequent use, depending on clinical indications.
Because of the retrospective nature of the study and the long study period, detailed cycle-level information regarding whether epididymal spermatozoa were used fresh or after cryopreservation and whether sperm used for ICSI originated from the contemporaneous PESA procedure or from a previously cryopreserved epididymal sperm sample was not consistently available in the medical records and therefore could not be evaluated reliably. Likewise, detailed quantitative data regarding specific commercial cryoprotective agents, post-thaw sperm survival rates, motility recovery profiles, and pre- versus post-PESA semen parameters were not consistently available and could not be analyzed. Nevertheless, only samples containing sufficient viable and motile spermatozoa for microinjection were used in ICSI treatment cycles.
Ovarian Stimulation, ICSI, and Embryo Transfer
Controlled ovarian hyperstimulation was performed using a GnRH antagonist protocol in all patients. Final oocyte maturation was triggered using either human chorionic gonadotropin alone or a dual trigger with human chorionic gonadotropin and a GnRH agonist. Transvaginal oocyte retrieval was performed 36 hours after trigger administration.
ICSI was performed using epididymal spermatozoa obtained via PESA. Fertilization was assessed 16–18 hours after ICSI, and normal fertilization was defined by the presence of two pronuclei (2PN). The actual oocyte-level fertilization rate was explicitly calculated and reported as the total number of 2PN embryos divided by the total number of metaphase II (MII) oocytes injected. Embryos were cultured under standard laboratory conditions.[9,10] Morphological assessment on Days 3 and 5 was performed using established morphological criteria consistent with the ESHRE/ALPHA Istanbul Consensus framework.[11] Embryo transfer was performed at either the cleavage stage (Day 3) or the blastocyst stage (Day 5), depending on embryo development. Transfers were performed either as fresh embryo transfers or in subsequent frozen–thawed embryo transfer (FET) cycles using embryos derived from the primary initiated PESA–ICSI cycle.
Outcome Measures
The primary outcome was the live birth rate per initiated PESA–ICSI cycle. Secondary outcomes included the oocyte-level fertilization rate, embryo transfer rate, clinical pregnancy rate, pregnancy loss rate, and live birth rate per embryo transfer. Clinical pregnancy was defined as the presence of an intrauterine gestational sac detected by transvaginal ultrasound.[12] Live birth was defined as the delivery of a live-born infant after 22 completed weeks of gestation.[12]
To ensure precise reporting, reproductive outcomes (clinical pregnancy and live birth) were analyzed using two separate denominators: per initiated cycle and per individual embryo transfer procedure. Total fertilization failure was defined as the complete absence of two pronuclei after ICSI. Pregnancy loss was defined as failure to achieve a live birth following a confirmed clinical pregnancy. All pregnancy losses observed in the present cohort were classified as miscarriages.
Statistical Analysis
Statistical analysis was performed using IBM SPSS Statistics software (IBM Corp., Armonk, NY, USA). Continuous variables were assessed for normality using the Shapiro–Wilk test and expressed as mean±standard deviation or median (interquartile range), as appropriate. Categorical variables were presented as numbers and percentages.
Clinical pregnancy and live birth rates were calculated both per initiated PESA–ICSI cycle and per embryo transfer procedure. Cycles without embryo transfer were included in cycle-based analyses but excluded from transfer-based analyses.
Comparisons between the obstructive azoospermia and ejaculatory dysfunction groups were performed using the chi-square test or Fisher’s exact test, as appropriate. Clinical pregnancy and live birth outcomes according to embryo developmental stage at transfer (Day 3 versus Day 5) were also compared using Fisher’s exact test. A two-sided p value<0.05 was considered statistically significant.
Results
Patient and Cycle Characteristics
A total of 63 PESA–ICSI cycles were performed in 46 male patients between January 2015 and December 2025. Each PESA–ICSI cycle was analyzed as a separate observational unit. The indications for PESA were erectile dysfunction, obstructive azoospermia, anejaculation, and retrograde ejaculation, as shown in Table 1.
Table 1.
Baseline demographic and clinical characteristics of the study cohort
| Variable | Value |
|---|---|
| Male age (years), mean±SD | 38.8±6.5 |
| Female age (years), mean±SD | 33.7±5.4 |
| Anti-müllerian hormone (ng/mL), median (IQR) | 0.81 (0.36–2.24) |
| Total gonadotropin dose (IU), median (IQR) | 2400 (2025–3300) |
| Number of oocytes retrieved, median (IQR) | 8 (3–14) |
| Number of MII oocytes, median (IQR) | 6 (3–11) |
| Number of fertilized oocytes (2PN), median (IQR) | 4 (2–6) |
| PESA indication, n (%) | |
| Erectile dysfunction | 34 (54.0%) |
| Obstructive azoospermia | 13 (20.6%) |
| Anejaculation | 11 (17.5%) |
| Retrograde ejaculation | 5 (7.9%) |
| Infertility etiology, n (%) | |
| Male factor | 33 (52.4%) |
| Diminished ovarian reserve | 10 (15.9%) |
| Male factor + diminished ovarian reserve | 8 (12.7%) |
| Unexplained infertility | 6 (9.5%) |
| Müllerian anomaly | 3 (4.8%) |
| Polycystic ovary syndrome | 2 (3.2%) |
| Tubal factor | 1 (1.6%) |
SD: Standard deviation; IQR: Interquartile range; MII: Metaphase II; 2PN: Two pronuclei; PESA: Percutaneous epididymal sperm aspiration; IU: International units.
Regarding infertility etiology, male factor infertility was present in 33 cycles (52.4%), diminished ovarian reserve in 10 cycles (15.9%), combined male factor and diminished ovarian reserve in 8 cycles (12.7%), unexplained infertility in 6 cycles (9.5%), Müllerian anomalies in 3 cycles (4.8%), polycystic ovary syndrome (PCOS) in 2 cycles (3.2%), and tubal factor infertility in 1 cycle (1.6%). Baseline demographic, ovarian stimulation, and embryological characteristics are summarized in Table 1.
Fertilization, Embryo Development, and Reproductive Outcomes
A total of 498 mature (MII) oocytes were injected across all cycles. Normal fertilization (2PN) was observed in 268 MII oocytes, yielding an oocyte-level fertilization rate of 53.8% (268/498). At the cycle level, at least one normally fertilized embryo was obtained in 62 of 63 PESA–ICSI cycles (98.4%), while total fertilization failure occurred in only one cycle (1.6%).
Embryo transfer was performed in 57 of 63 initiated cycles (90.5%). Embryo transfer was not performed in six cycles: one because of total fertilization failure, four because of embryo developmental arrest, and one in which a blastocyst was cryopreserved but transfer had not yet been performed. A total of 68 embryo transfer procedures were performed, including both fresh and frozen–thawed transfers.
Clinical pregnancy was achieved in 25 of 63 initiated cycles, corresponding to a clinical pregnancy rate of 39.7% per initiated cycle and 36.8% (25/68) per embryo transfer procedure. Live birth was achieved in 21 of 63 initiated cycles, resulting in a live birth rate of 33.3% per initiated cycle and 30.9% (21/68) per embryo transfer procedure. Pregnancy loss occurred in four clinical pregnancies, corresponding to a pregnancy loss rate of 16.0% (4/25). No multiple pregnancies were observed in the study cohort. These outcomes are summarized in Table 2.
Table 2.
Fertilization, embryo transfer, and reproductive outcomes of PESA–ICSI cycles
| Parameter | Value |
|---|---|
| Total initiated PESA–ICSI cycles, n | 63 |
| Cycles with normal fertilization (2PN), % (n/N) | 98.4% (62/63) |
| Oocyte-level fertilization rate, % (n/N) | 53.8% (268/498) |
| Total fertilization failure, % (n/N) | 1.6% (1/63) |
| Cycles resulting in at least one embryo transfer, % (n/N) | 90.5% (57/63) |
| Total embryo transfer procedures (Fresh + Thaw), n | 68 |
| Clinical pregnancy rate | |
| Per initiated cycle, % (n/N) | 39.7% (25/63) |
| Per embryo transfer, % (n/N)* | 36.8% (25/68) |
| Live birth rate | |
| Per initiated cycle, % (n/N) | 33.3% (21/63) |
| Per embryo transfer, % (n/N)* | 30.9% (21/68) |
| Pregnancy loss rate, % (n/N)** | 16.0% (4/25) |
Rates were calculated based on the total number of embryo transfer procedures performed (n=68) to differentiate sequential or repeated transfers derived from the same cycle. ** The pregnancy loss rate was calculated based on the total number of confirmed clinical pregnancies achieved (n=25). PESA: Percutaneous epididymal sperm aspiration; ICSI: Intracytoplasmic sperm injection; 2PN: Two pronuclei; n: Number of events; N: Total number of observations.
Surgical Safety and Complications
Regarding the surgical sperm retrieval procedure, no major intraoperative or postoperative complications, such as scrotal hematoma requiring evacuation, postprocedural infection, or severe persistent pain, were recorded in any of the 63 PESA procedures performed.
Reproductive Outcomes Stratified by PESA Indication
To evaluate the impact of the underlying sperm retrieval indication on clinical success, the cohort was stratified into two groups: obstructive azoospermia (OA, n=13) and ejaculatory dysfunction (ED, n=50). A total of 498 mature (MII) oocytes were injected (134 in the OA group and 364 in the ED group), yielding 268 normally fertilized (2PN) embryos (67 in the OA group and 201 in the ED group). The oocyte-level fertilization rate did not differ significantly between the OA and ED groups (50.0% vs. 55.2%, respectively; p=0.312).
Regarding cycle-based clinical outcomes, the clinical pregnancy rate per cycle was 15.4% (2/13) in the OA group and 46.0% (23/50) in the ED group (p=0.059). Similarly, the live birth rate per cycle was 15.4% (2/13) in the OA group and 38.0% (19/50) in the ED group (p=0.189). These comparative outcomes are summarized in Table 3.
Table 3.
Embryological and cycle-based reproductive outcomes stratified by PESA indication
| Parameters / Clinical Outcomes | Total Cohort (n=63) | Obstructive Azoospermia (n=13) | Ejaculatory Dysfunction (n=50) | p |
|---|---|---|---|---|
| Embryological Parameters | ||||
| Total mature (MII) oocytes injected | 498 | 134 | 364 | — |
| Total normal fertilization (2PN) embryos | 268 | 67 | 201 | — |
| Oocyte-level fertilization rate, % (n/N) | 53.8% (268/498) | 50.0% (67/134) | 55.2% (201/364) | 0.312 |
| Cycle-Based Success Rates | ||||
| Clinical pregnancy rate per cycle, % (n/N) | 39.7% (25/63) | 15.4% (2/13) | 46.0% (23/50) | 0.059 |
| Live birth rate per cycle, % (n/N) | 33.3% (21/63) | 15.4% (2/13) | 38.0% (19/50) | 0.189 |
Ejaculatory dysfunction includes patients with severe erectile dysfunction, anejaculation, and retrograde ejaculation. PESA: Percutaneous epididymal sperm aspiration; MII: Metaphase II; 2PN: Two pronuclei; n: Number of events; N: Total number of observations.
Reproductive Outcomes According to Transfer Type and Embryo Developmental Stage
Clinical outcomes were evaluated according to the type of embryo transfer (fresh versus frozen–thawed) and the embryonic developmental stage at transfer (Day 3 versus Day 5). Among fresh embryo transfer procedures, clinical pregnancy was achieved in 16 of 42 transfers (38.1%), resulting in a live birth rate of 33.3% (14/42). In frozen–thawed embryo transfer procedures, the clinical pregnancy rate was 34.6% (9/26), with a live birth rate of 26.9% (7/26).
When analyzed according to embryo developmental stage, Day 3 (cleavage-stage) embryo transfers resulted in a clinical pregnancy rate of 40.5% (15/37) and a live birth rate of 29.7% (11/37). Day 5 (blastocyst-stage) embryo transfers yielded a clinical pregnancy rate of 32.3% (10/31) and a live birth rate of 32.3% (10/31). No statistically significant differences were observed between cleavage-stage and blastocyst-stage transfers with respect to clinical pregnancy rates (p=0.615) or live birth rates (p=1.000). These comparative reproductive outcomes are summarized in Table 4.
Table 4.
Clinical pregnancy and live birth outcomes stratified by transfer type and embryo developmental stage
| Transfer Type / Stage | Embryo Transfer Procedures (n=68) | Clinical Pregnancy Rate, % (n/N) | Live Birth Rate, % (n/N) |
|---|---|---|---|
| Transfer Type | |||
| Fresh embryo transfer | 42 | 38.1% (16/42) | 33.3% (14/42) |
| Frozen–thawed embryo transfer | 26 | 34.6% (9/26) | 26.9% (7/26) |
| Embryo Stage | |||
| Day-3 embryo transfer (cleavage) | 37 | 40.5% (15/37) | 29.7% (11/37) |
| Day-5 embryo transfer (blastocyst) | 31 | 32.3% (10/31) | 32.3% (10/31) |
| p-value* | 0.615* | 1.000* |
Fisher’s exact test comparing cleavage-stage and blastocyst-stage embryo transfers. n: Number of events; N: Total number of observations.
Discussion
This study evaluated reproductive outcomes following PESA–ICSI over an 11-year period at a single tertiary referral center. The findings indicate that PESA-derived epididymal sperm can provide favorable embryological and reproductive outcomes across diverse clinical indications. In the overall cohort, the oocyte-level fertilization rate was 53.8%, while the clinical pregnancy and live birth rates per initiated cycle were 39.7% and 33.3%, respectively. When analyzed per embryo transfer procedure, the clinical pregnancy rate was 36.8%, and the live birth rate was 30.9% (Table 2). These outcomes are broadly consistent with those reported in contemporary PESA–ICSI cohorts and large surgical sperm retrieval studies.[3,6–8] These findings support the clinical utility of epididymal sperm retrieved by PESA in modern assisted reproductive practice.
An important characteristic of the present cohort was the relatively compromised ovarian reserve profile of the female partners, reflected by a median anti-Müllerian hormone (AMH) level of 0.81 ng/mL. Diminished ovarian reserve is generally associated with lower oocyte yield, reduced embryo availability, and lower cumulative live birth rates. Despite this unfavorable female reproductive profile, the observed clinical pregnancy and live birth rates remained within the range reported in previous PESA–ICSI studies.[3,6–8] This finding suggests that acceptable reproductive outcomes can be achieved using PESA-derived spermatozoa even in cohorts with less favorable ovarian reserve characteristics. Previous comparative studies have also shown that fertilization and pregnancy outcomes using epididymal sperm are comparable to those achieved using testicular spermatozoa.[1,2,4,6,8]
Another major finding relates to the distribution of clinical indications for PESA. While historical series have predominantly focused on percutaneous aspiration for classic anatomic obstructive azoospermia (OA), the majority of procedures in our cohort were performed for severe, refractory ejaculatory dysfunction (ED), including organic erectile dysfunction and anejaculation. Fang et al.[7] previously demonstrated that PESA–ICSI serves as a highly effective intervention for couples experiencing orgasmic or ejaculatory failure, yielding robust fertilization and pregnancy outcomes.
When our dataset was explicitly stratified according to the primary etiology (obstructive azoospermia vs. ejaculatory dysfunction), formal statistical testing revealed no significant differences in the oocyte-level fertilization rate (50.0% vs. 55.2%, p=0.312) or cycle-based live birth rates (15.4% vs. 38.0%, p=0.189) (Table 3). These findings suggest that comparable reproductive outcomes can be achieved across different indications for PESA, including obstructive azoospermia and severe ejaculatory dysfunction.
Sperm retrieval was completely successful in all cycles evaluated in this study. This 100% surgical success rate underscores the technical reproducibility of PESA when performed using a standardized approach by a single experienced urologist, minimizing the multi-operator technical confounding factors that often bias multicenter series.[3–5,8]
To directly address editorial and reviewer queries regarding the safety and tolerability of the surgical approach, a systematic review of our urological and clinical records was performed. The documentation revealed no immediate or delayed major procedural complications. Specifically, no cases of postprocedural scrotal hematoma requiring surgical evacuation, secondary infection, or severe persistent pain were recorded. The absence of major recorded complications in this cohort supports the feasibility of PESA as a minimally invasive sperm retrieval technique. In clinical practice, standardized morphological evaluation is not routinely performed for surgically retrieved epididymal sperm specimens at our facility because these samples are intended exclusively for ICSI, for which the presence of an adequate volume of viable and motile spermatozoa for microinjection serves as the primary laboratory criterion.
Embryo developmental stage at the time of transfer was also evaluated in relation to reproductive outcomes. Clinical pregnancy rates were 40.5% following Day 3 (cleavage-stage) embryo transfers and 32.3% following Day 5 (blastocyst-stage) embryo transfers. Corresponding live birth rates were 29.7% and 32.3%, respectively (Table 4). No statistically significant differences were observed between cleavage-stage and blastocyst-stage transfers with respect to either clinical pregnancy (p=0.615) or live birth outcomes (p=1.000). Although previous studies have suggested that blastocyst-stage transfer may improve clinical pregnancy and live birth outcomes in selected good-prognosis populations,[13,14] such an advantage was not demonstrated in the present cohort. This finding should be interpreted within the clinical context of the study population, as the embryo developmental stage at transfer may be influenced by embryo availability, ovarian reserve status, and clinical transfer strategy.
Clinical pregnancy and live birth rates reached 38.1% and 33.3%, respectively, following fresh embryo transfer procedures, compared with 34.6% and 26.9%, respectively, following frozen–thawed embryo transfer procedures (Table 4). Although the present study was not specifically designed to compare embryo transfer strategies, the observed outcomes suggest that satisfactory reproductive results can be achieved following both fresh and frozen–thawed embryo transfer procedures derived from PESA–ICSI cycles. These observations are consistent with previous studies reporting favorable reproductive outcomes following PESA–ICSI.[6,8] However, because the retrospective database did not consistently document whether epididymal spermatozoa were used fresh or after cryopreservation for each individual treatment cycle, the present findings should not be interpreted as a comparison of fresh versus cryopreserved epididymal sperm use.
Over the 11-year span of this study, progressive advancements in laboratory infrastructure, including the optimization of single-step culture media and the implementation of highly stable physiological incubation systems, took place in our IVF facility.[9,10] While these refinements naturally contributed to the temporal stabilization of embryo culture conditions,[10] the favorable fertilization outcomes observed in this cohort support the continued clinical utility of epididymal spermatozoa in ICSI cycles despite gradual laboratory improvements.
Limitations
Several limitations of this study must be explicitly acknowledged. First, the study relies on a retrospective design from a single center, which carries inherent risks of selection bias and lacks the prospective randomization of a controlled trial. Second, following clinical stratification, a significant numerical imbalance was present between the ejaculatory dysfunction (n=50) and obstructive azoospermia (n=13) groups, reflecting the specific referral patterns of our tertiary referral center; this uneven distribution limits the statistical power to detect subtle differences between the cohorts. Third, because multiple treatment cycles from the same patient were analyzed as separate observational units, the potential nonindependence of repeated cycles cannot be completely excluded and may have influenced outcome estimates. In addition, patient-level cumulative live birth outcomes were not evaluated, which may limit the interpretation of overall treatment success across repeated treatment cycles. Fourth, owing to the retrospective nature of the database, detailed quantitative records regarding specific commercial cryoprotectant brands, post-thaw sperm survival rates, motility recovery percentages, and other detailed sperm quality parameters were not consistently available and therefore could not be formally analyzed. Fifth, procedural complications were identified retrospectively from routine clinical documentation rather than through standardized prospective assessment. Consequently, minor pain, failed aspiration attempts, morbidity associated with repeated procedures, and other minor adverse events may have been underreported. Finally, our dataset lacks long-term pediatric follow-up or health tracking of children born following these procedures.
Conclusion
In conclusion, PESA–ICSI is associated with favorable fertilization, clinical pregnancy, and live birth outcomes. These results were achieved in a real-world single-center cohort characterized by low baseline ovarian reserve and a high proportion of severe, medically refractory ejaculatory disorders. The 100% sperm retrieval rate and the absence of major recorded surgical complications in this cohort support the technical reproducibility of the procedure. These findings support the continued use of PESA as an effective sperm retrieval technique in contemporary assisted reproductive practice, particularly for patients presenting with ejaculatory failure.
Footnotes
Please cite this article as ”Yetkinel S, Ozer C, Kayra MV, Caglar Aytac P, Dogan Durdag G, Alkas Yaginc D, et al. Intracytoplasmic Sperm Injection Outcomes Using Epididymal Sperm Obtained by Percutaneous Aspiration: An 11-Year Single-Center Experience. Med Bull Sisli Etfal Hosp 2026;60(3):338-345”.
Disclosures
Ethics Approval
Ethics committee approval for this study was obtained from the Baskent University Institutional Review Board (Project No: KA26/204; approval date: April 21, 2026).
Informed Consent
Not applicable due to the retrospective nature of the study and the use of anonymized clinical data.
Conflict of Interest
The authors declare that there is no conflict of interest.
Financial Disclosure
The study was supported by the Baskent University Research Fund.
Use of AI for Writing Assistance
The authors declare that no artificial intelligence (AI)-assisted technologies were used in the preparation of this manuscript.
Authorship Contributions
Concept – S.Y., C.O.; Design – S.Y., C.O.; Supervision – C.O.; Materials – E.S.; Data collection &/or processing – D.A.Y., M.V.K.; Analysis and/or interpretation – P.C.A., G.D.D.; Literature search – S.Y.; Writing – S.Y.; Critical review – P.C.A., G.D.D.
Peer-review
Externally peer-reviewed.
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