- Email: [email protected]
Identification of motile sperm in caput epididymis
STERILITY-FERTILITY
IDENTIFICATION OF MOTILE SPERM IN CAPUT EPIDIDYMIS Intraoperative
Observations and Clinical Correlations
BRAD WOLFSON, M.D. JOSEPH GAMBONE, M.D. JACOB RAJFER, M.D.
From the Division of Urology, Department of Surgery, and Department of Obstetrics and Gynecology, UCLA School of Medicine, Los Angeles, California
ABSTRACT-This retrospective review of patients who underwent vasoepididymostomy demonstrates that motile sperm may be identified in the most proximal portion of the epididymis, and implies that induction of sperm motility may be independent of transit through the epididymis. Although further studies are needed, the data imply that it may not be necessary to identify motile sperm in the epididymal fluid to achieve a successful vasoepididymostomy.
It is generally believed that maturation of sperm, in particular the development of their motility, occurs as they traverse the length of the epididymis. 1-g This tenet supports the hypothesis that sperm emerging from the rete testis, the most proximal portion of the epididymis, are not yet capable of fertilization and that fertilizing ability is accrued as sperm pass through the epididymis. Arguments still exist as to whether these changes are intrinsic to the sperm or are dependent on extrinsic epididymal factors 2.4,6,8.10-13 However, as in vitro fertilization processes become more common, our knowledge of sperm function is undergoing significant changes. Recent studies by Silber12-14 and his colleagues have identified sperm from the most proximal portion of the epididymis which are capable of oocyte fertilization, thereby suggesting that the initiation of sperm motility in the human epididymis may occur in the head (caput) of the epididymis, in the vasa efferentia, or even more proximally, rather than in the body (corpus) or tail (cauda) of the epididymis. These findings prompted the successful use of sperm from the most proximal portion of the epididymis for in vitro fertilization and support
UROLOGY
/
OCTOBER
1992
/ VOLUME
40, NUMBER 4
the validity of using the rete testis or proximal epididymal tubule as potential sites for vasoepididymostomy in patients undergoing reconstructive surgery on the epididymis.ll,ls These observations prompted us to ask whether or not sperm from the most proximal portion of the epididymis are motile, and whether or not it is necessary to identify motile sperm in the epididymal fluid prior to vasoepididymostomy to obtain adequate motility postoperatively. To gain further insight into these questions, we retrospectively investigated epididymal sperm motility in 43 patients who underwent vasoepididymostomy for obstructive azoospermia, and for lack of a better control group, compared these with the findings in nonobstructed men undergoing bilateral orchiectomy for prostate carcinoma. When available, post procedure semen analyses in the vasoepididymostomy group were reviewed and correlated with the intraoperative findings. Material and Methods The medical records of 43 men (mean age 40 years) who underwent vasoepididymostomy at our institution between 1985 and 1989 were reviewed (Fig. 1). Etiology of the epididymal
335
TABLE I. Results of 65 vasoepididymostomies
30 VE only
22VElVE
(44 VE)
Anastomosis Level
13VElVV
8VE/O
(8 VE)
Cauda 38 (59) Corpus 12 (18) Caput 15 (23) TOTALS 65
I
(13 VE)
Total = 65 VE FIGURE 1. Study group of 43 cases (VE didymostomy, VV = vasovasostomy).
= vasoepi-
obstruction was congenital in 14 and secondary to vasectomy in 29. Of these 43 cases, 13 were a combined vasoepididymostomy, that is a vasoepididymostomy on one side and a vasovasostomy on the contralateral side. The remaining 30 men underwent vasoepididymostomy only, and of these 22 had bilateral vasoepididymostomies. The other 8 had unilateral vasoepididymostomy which was mainly due to absence of the testis or epididymis on the contralateral side. Thus a total of 65 vasoepididymostomies were performed, and our observations of these 65 epididymides form the basis of this report. Since these patients represented an obstructed group and because an age-matched control group is not feasible, a nonage-matched control group was selected for statistical comparison. This consisted of 5 men (mean age 68 years) who underwent bilateral orchiectomy for Stage D2 carcinoma of the prostate. These men had no previous vasectomy or prostate surgery and semen analyses were not performed preoperatively in these subjects. Only 9 of the epididymides in these 5 patients were available for evaluation, since one was excluded because of a large spermatocele in the proximal portion of the epididymis. Vasoepididymostomy was performed as described previously by Silber. l7 Briefly, the epididymis was meticulously dissected from the testis, and the epididymis was then serially transected at 0.5-cm intervals from the cauda epididymis through the corpus and into the caput epididymis. At each transection, fluid from an epididymal tubule was inspected grossly under the operating microscope, and then under the light microscope at high power (40 x ) looking at sperm quality and motility. The motility was not graded. In most of our patients, if the 336
Sperm (% ) -WholParts Non-motile
None 6 (16) 0 4 (27) 10 (16)
1 2 1 4
(3) (17) (6) (6)
Motile
21 (55)
10 (26)
7 (58) 6 (40) 34 (52)
3 (25) 4 (27) 17 (26)
fluid was grossly clear, or if the fluid was turbid yet contained whole sperm on microscopic examination, vasoepididymostomy was performed at that level. In the control group, the epididymis was transected in its most proximal portion immediately following orchiectomy. Fluid from these epididymal tubules was inspected under the light microscope at high power (40 x ), and the presence of sperm motility was recorded, but not graded. Results In our group of 65 vasoepididymostomies, the level of anastomosis was to the cauda in 38 (59%), the corpus in 12 (18%), and the caput in 15 (23 %) (Table I). Fluid from the epididymal tubule at the time of anastomosis showed no sperm in 10 (16 % ), sperm parts in 4 (6 % ), whole but non-motile sperm in 34 (52%), and whole motile sperm in 17 (26%). Of the 65 vasoepididymostomies performed, motile sperm were identified at all levels of the epididymis. In the caput, 10 of 38 (27 %) had motile sperm, in the corpus 3 of 12 (25 % ) , and in the cauda 4 of 15 (26%) had motile sperm. In our nonagematched control group, motile sperm were seen in 8 of 9 (89%) caput epididymides. In the group of 30 men who underwent vasoepididymostomy only, 9 had motile sperm in the epididymal tubule as the time of the procedure. Of these 7 had a semen analysis performed at least three months following vasoepididymostomy. The analysis showed azoospermia in 3, oligospermia in 1, and a normal sperm count in 3 (Fig. 2). Two of the 3 men with normal counts have induced term pregnancies .
Twenty-one of the 30 men had a vasoepididymostomy when motile sperm were not identified in the epididymal fluid. Of these 21, 15 had a semen analysis performed at least three months following the procedure. The analysis showed azoospermia in 9 and a normal sperm count in 6. Of those with a normal sperm
UROLOGY
/ OCTOBER1992
/ VOLUME40.NUMBER4
30 VE only 9 Mot-motile I
7 S.A. (3 mo) Azo -I 3 Oligo - 1 Nml --- 3
-1
15 S.A. (3 mo) Azo -‘9 Nml - 6 S.P. ---- 2 Whole - 4
FIGURE 2. Post vasoepididymostomy semen analysis (VE = vasoepididymostomy, SA = semen analysis, SP = sperm parts.)
count, the epididymal fluid at the time of vasoepididymostomy showed sperm parts in 2, and whole but non-motile sperm in 4 (Fig. 2). There have been three term pregnancies induced by these men, and all three were noted to have whole but non-motile sperm identified in the epididymal fluid at the time of vasoepididymostomy. Comment Controversy remains regarding the fertilizing ability of sperm emerging from the testis and whether factors extrinsic to the sperm are necessary for continued development as it passes through the epididymis. Numerous animal studies have been performed to address these questions. Young9 evaluated ligated epididymides in the guinea pig and concluded that (1) the time consumed by sperm in passing through the epididymis is necessary for the completion of their development, (2) morphologic and functional changes in the sperm which occur during this period are not dependent on epididyma1 factors, and (3) regressive changes including decreased motility and reduced fertilizing ability follow attainment of optimal function. Gaddum and Glover3 found similar changes in the ligated rabbit epididymis, including an increased sperm motility proximal to the obstructed epididymis. Paufler and Foote7 recognized an increase in caput epididymal sperm motility after ligation which regressed over time. Gaddum4 studied sperm motility in the rabbit epididymis. Sperm from the vasa efferentia showed only weak vibratory movements with no forward progression, while proximal caput sperm had weak circular motion which changed to a sudden increased activity in the distal caput. An increase in progressive forward motion was observed in sperm isolated more
UROLOGY
I OCTOBER1992
/ VOLUME40,NUMBER4
distally in the corpus and cauda epididymis. Bedford2 similarly studied sperm motility in the human and found that sperm from the caput epididymis had only weak vibrating movement with the exception of a few which displayed thrashing tail motion and mild forward progression. The number with thrashing motion increased until the mid corpus where a dramatic increase in the capacity for sustained progressive forward motility occurred. The results of our control group showed that the majority of nonobstructed epididymides had motile sperm in the caput epididymis (89 %). In the study group of obstructed epididymides, only 26 percent had motile sperm, despite a varied level of obstruction. In fact, the distribution of motile sperm was nearly equal among the caput (27 % ), corpus (25 % ) , and cauda epididymis (24 % ) . These results may not represent the true incidence of motile sperm in these epididymides, as vasoepididymostomy was often performed (particularly in the earlier part of our series) at a level where clear fluid was seen emanating from the epididymal tubule, regardless of the sperm morphology or motility. During the more recent part of our series, it has become obvious to us that if we would have transected the epididymis more proximally in these earlier patients, the sperm morphology and motility would have improved in a significant number of epididymides. Thus obstruction of the epididymis may not play a role in the inhibition of sperm motility as initially suggested by Young.g Since our observations suggest that although epididymal fluid from tubules immediately proximal to an area of obstruction may demonstrate poor sperm morphology and motility, improved sperm parameters can be observed in fluid from a more proximal portion of that epididymis. Even in those epididymides which demonstrated no motile sperm in the caput epididymis, it is possible that motile sperm might have been observed in the more proximal vasa efferentia. These observations have prompted us to inspect the fluid emanating from the transected epididymal tubules during vasoepididymostomy to identify the presence and motility of sperm. When whole motile sperm are identified, vasoepididymostomy is performed at that level. When vasovasostomy has been performed on the contralateral side, or when the opposite side is not available for anastomosis, it was our custom in the past to perform a vasoepididymostomy without identifying motile sperm.
337
Since animal and human studies have shown a positive correlation between fertility rate and the distance from the vasa efferentia to the level of vasoepididymostomy, sacrificing extra length of epididymis to identify motile sperm remains an issue of discussion.1,5-7J2 SilberlO reported on 5 patients who underwent bilateral vasoepididymostomy to the caput epididymis. Initial sperm analysis showed O-l percent motility, but by 1.5 years 4 of 5 had normal sperm motility, Further studies showed significant fertility rates could be achieved with vasoepididymostomy to the caput epididymis (31% ) . l2 The fertility rate correlated well with the sperm motility on follow-up postoperative semen analyses; those with motility less than 20 percent had a fertility rate of 15 percent, while those with motility more than 20 percent had a fertility rate of 58 percent. Significant time (up to 2 years) was required to regain these sperm motilities, and in some of our patients it has taken greater than one year to observe the return of normal sperm counts and motility. In our group of 30 men who underwent vasoepididymostomy only, 21 had non-motile sperm (whole sperm or sperm parts) identified in the epididymal fluid at the time of the procedure. Of the 15 men who had a semen analysis performed at least three months following the procedure, 6 were noted to have normal sperm count. The level of vasoepididymostomy in these 6 patients was to the caput in 1, the corpus in 1, and the cauda in 4, while the epididymal fluid at the time of vasoepididymostomy showed whole but non-motile sperm in 4 of these patients, and sperm parts in 2. Postoperative sperm motility was regained in 5 of 6 (80 %), and 3 of 6 had motility more than 20 percent. There have been three term pregnancies induced by these men, and all three were noted to have whole but non-motile sperm identified in the epididymal fluid at the time of vasoepididymostomy. Thus the return of sperm motility can be observed when vasoepididymostomy is performed at any level of the epididymis and when whole but non-motile sperm or sperm parts are identified in the epididymal fluid at the time of the procedure. However, in our relatively small series, fertilizing ability has been documented only when whole motile or non-motile sperm, rather than sperm parts, are observed in the epididymal fluid. From these retrospective observations, our data suggest that sperm motility may be achieved within or proximal to the caput epi-
338
didymis in both obstructed and nonobstructed epididymides. The fact that normal sperm counts, motility, and subsequent pregnancy were obtained following vasoepididymostomy to an epididymal tubule where the sperm were whole but non-motile, implies that it may not be necessary to identify motile sperm in the epididymal fluid prior to vasoepididymostomy. Although further studies are needed to discern the epididymal level and epididymal fluid characteristics which optimize the chance for in vivo fertilization, our data suggest that in the performance of a vasoepididymostomy, the level of the epididymis which should be selected is the level which contains whole sperm, regardless of their motility, even if this requires incising into the most proximal portion of the epididymis. Los Angeles, California 90024 (DR. WOLFSON) References 1. Bedford JM: Development of the fertilizing ability of spermatozoa in the epididymis of the rabbit, J Exp Zoo1 163: 319 (1966). 2. Bedford JM: The maturation of spermatozoa in the human epididymis, J keprod Fertil (Suppl) 18: 199 (1973). 3. Gaddum I’. and Glover T: Some reactions of rabbit soermatozoa to ligation’of the epididymis, J Reprod Fertil9: 119 11965). 4. Gaddum P: Sperm maturation in the male reproductive tract: development of motility, Anat Ret 161: 471 (1968). 5. Horan AH, and Bedford JM: Development of the fertilizing ability of the spermatozoa in the epididymis of the Syrian hamster, J Reprod Fertil 30: 417 (1972). 6. Orgebin-Christ MC: Studies on the function of the epididymis, Biol Reprod (Suppl) 1: 155 (1972). 7. Paufler SK, and Foote RH: Morphology, motility, and fertility of spermatozoa recovered from different areas of ligated rabbit epididymides, J Reprod Fertil 17: 125 (1968). 8. Schoysman RJ, and Bedford JM: The role of the human epididymis in sperm maturation and sperm storage as reflected in the consequences of epididymovasostomy, Fertil Steri146: 293 (1986). 9. Young WC: A study of the function of the epididymis. III. Functional changes undergone by spermatozoa during their passage through the epididymis and vas deferens in the guinea pig, J Exp Biol 8: 151 (1931). 10. Silber SJ: Vasoepididymostomy to the head of the epididymis: recovery of normal spermatozoa1 motility, Fertil Steril 34: 149 (1980). 11. Silber SJ: Pregnancy with sperm aspiration from the proximal head of the epididymis: a new treatment for congenital absence of the vas deferens, Fertil Steril 50: 525 (1988). 12. Silber SJ: Results of microsurgical vasoepididymostomy: role of epididymis in sperm maturation, Hum Reprod 4: 298 (1989). 13. Silber SJ: Apparent fertility of human spermatozoa from the caput epididymis, J Androl 10: 263 (1989). 14. Silber SJ: Pregnancy caused by sperm from vasa efferentia, Fertil Steril 49: 373 (1988). 15. Wyker R, and Howards SS: Micropuncture studies of the motility of rete testis and epididymal spermatozoa, Fertil Steril 28: 108 (1977). 16. Jequier AM, et al: A pregnancy achieved using sperm from the epididymal caput in idiopathic obstructive azoospermia, Fertil Steril 53: 1104 (1990). 17. Silber SJ: Microscopic vasoepididymostomy: specific microanastomosis to the epididymal tubule, Fertil Steril 30: 565 (1978).
UROLOGY
I
OCTOBER
1992
I
VOLUME 40, NUMBER 4
IDENTIFICATION OF MOTILE SPERM IN CAPUT EPIDIDYMIS Intraoperative
Observations and Clinical Correlations
BRAD WOLFSON, M.D. JOSEPH GAMBONE, M.D. JACOB RAJFER, M.D.
From the Division of Urology, Department of Surgery, and Department of Obstetrics and Gynecology, UCLA School of Medicine, Los Angeles, California
ABSTRACT-This retrospective review of patients who underwent vasoepididymostomy demonstrates that motile sperm may be identified in the most proximal portion of the epididymis, and implies that induction of sperm motility may be independent of transit through the epididymis. Although further studies are needed, the data imply that it may not be necessary to identify motile sperm in the epididymal fluid to achieve a successful vasoepididymostomy.
It is generally believed that maturation of sperm, in particular the development of their motility, occurs as they traverse the length of the epididymis. 1-g This tenet supports the hypothesis that sperm emerging from the rete testis, the most proximal portion of the epididymis, are not yet capable of fertilization and that fertilizing ability is accrued as sperm pass through the epididymis. Arguments still exist as to whether these changes are intrinsic to the sperm or are dependent on extrinsic epididymal factors 2.4,6,8.10-13 However, as in vitro fertilization processes become more common, our knowledge of sperm function is undergoing significant changes. Recent studies by Silber12-14 and his colleagues have identified sperm from the most proximal portion of the epididymis which are capable of oocyte fertilization, thereby suggesting that the initiation of sperm motility in the human epididymis may occur in the head (caput) of the epididymis, in the vasa efferentia, or even more proximally, rather than in the body (corpus) or tail (cauda) of the epididymis. These findings prompted the successful use of sperm from the most proximal portion of the epididymis for in vitro fertilization and support
UROLOGY
/
OCTOBER
1992
/ VOLUME
40, NUMBER 4
the validity of using the rete testis or proximal epididymal tubule as potential sites for vasoepididymostomy in patients undergoing reconstructive surgery on the epididymis.ll,ls These observations prompted us to ask whether or not sperm from the most proximal portion of the epididymis are motile, and whether or not it is necessary to identify motile sperm in the epididymal fluid prior to vasoepididymostomy to obtain adequate motility postoperatively. To gain further insight into these questions, we retrospectively investigated epididymal sperm motility in 43 patients who underwent vasoepididymostomy for obstructive azoospermia, and for lack of a better control group, compared these with the findings in nonobstructed men undergoing bilateral orchiectomy for prostate carcinoma. When available, post procedure semen analyses in the vasoepididymostomy group were reviewed and correlated with the intraoperative findings. Material and Methods The medical records of 43 men (mean age 40 years) who underwent vasoepididymostomy at our institution between 1985 and 1989 were reviewed (Fig. 1). Etiology of the epididymal
335
TABLE I. Results of 65 vasoepididymostomies
30 VE only
22VElVE
(44 VE)
Anastomosis Level
13VElVV
8VE/O
(8 VE)
Cauda 38 (59) Corpus 12 (18) Caput 15 (23) TOTALS 65
I
(13 VE)
Total = 65 VE FIGURE 1. Study group of 43 cases (VE didymostomy, VV = vasovasostomy).
= vasoepi-
obstruction was congenital in 14 and secondary to vasectomy in 29. Of these 43 cases, 13 were a combined vasoepididymostomy, that is a vasoepididymostomy on one side and a vasovasostomy on the contralateral side. The remaining 30 men underwent vasoepididymostomy only, and of these 22 had bilateral vasoepididymostomies. The other 8 had unilateral vasoepididymostomy which was mainly due to absence of the testis or epididymis on the contralateral side. Thus a total of 65 vasoepididymostomies were performed, and our observations of these 65 epididymides form the basis of this report. Since these patients represented an obstructed group and because an age-matched control group is not feasible, a nonage-matched control group was selected for statistical comparison. This consisted of 5 men (mean age 68 years) who underwent bilateral orchiectomy for Stage D2 carcinoma of the prostate. These men had no previous vasectomy or prostate surgery and semen analyses were not performed preoperatively in these subjects. Only 9 of the epididymides in these 5 patients were available for evaluation, since one was excluded because of a large spermatocele in the proximal portion of the epididymis. Vasoepididymostomy was performed as described previously by Silber. l7 Briefly, the epididymis was meticulously dissected from the testis, and the epididymis was then serially transected at 0.5-cm intervals from the cauda epididymis through the corpus and into the caput epididymis. At each transection, fluid from an epididymal tubule was inspected grossly under the operating microscope, and then under the light microscope at high power (40 x ) looking at sperm quality and motility. The motility was not graded. In most of our patients, if the 336
Sperm (% ) -WholParts Non-motile
None 6 (16) 0 4 (27) 10 (16)
1 2 1 4
(3) (17) (6) (6)
Motile
21 (55)
10 (26)
7 (58) 6 (40) 34 (52)
3 (25) 4 (27) 17 (26)
fluid was grossly clear, or if the fluid was turbid yet contained whole sperm on microscopic examination, vasoepididymostomy was performed at that level. In the control group, the epididymis was transected in its most proximal portion immediately following orchiectomy. Fluid from these epididymal tubules was inspected under the light microscope at high power (40 x ), and the presence of sperm motility was recorded, but not graded. Results In our group of 65 vasoepididymostomies, the level of anastomosis was to the cauda in 38 (59%), the corpus in 12 (18%), and the caput in 15 (23 %) (Table I). Fluid from the epididymal tubule at the time of anastomosis showed no sperm in 10 (16 % ), sperm parts in 4 (6 % ), whole but non-motile sperm in 34 (52%), and whole motile sperm in 17 (26%). Of the 65 vasoepididymostomies performed, motile sperm were identified at all levels of the epididymis. In the caput, 10 of 38 (27 %) had motile sperm, in the corpus 3 of 12 (25 % ) , and in the cauda 4 of 15 (26%) had motile sperm. In our nonagematched control group, motile sperm were seen in 8 of 9 (89%) caput epididymides. In the group of 30 men who underwent vasoepididymostomy only, 9 had motile sperm in the epididymal tubule as the time of the procedure. Of these 7 had a semen analysis performed at least three months following vasoepididymostomy. The analysis showed azoospermia in 3, oligospermia in 1, and a normal sperm count in 3 (Fig. 2). Two of the 3 men with normal counts have induced term pregnancies .
Twenty-one of the 30 men had a vasoepididymostomy when motile sperm were not identified in the epididymal fluid. Of these 21, 15 had a semen analysis performed at least three months following the procedure. The analysis showed azoospermia in 9 and a normal sperm count in 6. Of those with a normal sperm
UROLOGY
/ OCTOBER1992
/ VOLUME40.NUMBER4
30 VE only 9 Mot-motile I
7 S.A. (3 mo) Azo -I 3 Oligo - 1 Nml --- 3
-1
15 S.A. (3 mo) Azo -‘9 Nml - 6 S.P. ---- 2 Whole - 4
FIGURE 2. Post vasoepididymostomy semen analysis (VE = vasoepididymostomy, SA = semen analysis, SP = sperm parts.)
count, the epididymal fluid at the time of vasoepididymostomy showed sperm parts in 2, and whole but non-motile sperm in 4 (Fig. 2). There have been three term pregnancies induced by these men, and all three were noted to have whole but non-motile sperm identified in the epididymal fluid at the time of vasoepididymostomy. Comment Controversy remains regarding the fertilizing ability of sperm emerging from the testis and whether factors extrinsic to the sperm are necessary for continued development as it passes through the epididymis. Numerous animal studies have been performed to address these questions. Young9 evaluated ligated epididymides in the guinea pig and concluded that (1) the time consumed by sperm in passing through the epididymis is necessary for the completion of their development, (2) morphologic and functional changes in the sperm which occur during this period are not dependent on epididyma1 factors, and (3) regressive changes including decreased motility and reduced fertilizing ability follow attainment of optimal function. Gaddum and Glover3 found similar changes in the ligated rabbit epididymis, including an increased sperm motility proximal to the obstructed epididymis. Paufler and Foote7 recognized an increase in caput epididymal sperm motility after ligation which regressed over time. Gaddum4 studied sperm motility in the rabbit epididymis. Sperm from the vasa efferentia showed only weak vibratory movements with no forward progression, while proximal caput sperm had weak circular motion which changed to a sudden increased activity in the distal caput. An increase in progressive forward motion was observed in sperm isolated more
UROLOGY
I OCTOBER1992
/ VOLUME40,NUMBER4
distally in the corpus and cauda epididymis. Bedford2 similarly studied sperm motility in the human and found that sperm from the caput epididymis had only weak vibrating movement with the exception of a few which displayed thrashing tail motion and mild forward progression. The number with thrashing motion increased until the mid corpus where a dramatic increase in the capacity for sustained progressive forward motility occurred. The results of our control group showed that the majority of nonobstructed epididymides had motile sperm in the caput epididymis (89 %). In the study group of obstructed epididymides, only 26 percent had motile sperm, despite a varied level of obstruction. In fact, the distribution of motile sperm was nearly equal among the caput (27 % ), corpus (25 % ) , and cauda epididymis (24 % ) . These results may not represent the true incidence of motile sperm in these epididymides, as vasoepididymostomy was often performed (particularly in the earlier part of our series) at a level where clear fluid was seen emanating from the epididymal tubule, regardless of the sperm morphology or motility. During the more recent part of our series, it has become obvious to us that if we would have transected the epididymis more proximally in these earlier patients, the sperm morphology and motility would have improved in a significant number of epididymides. Thus obstruction of the epididymis may not play a role in the inhibition of sperm motility as initially suggested by Young.g Since our observations suggest that although epididymal fluid from tubules immediately proximal to an area of obstruction may demonstrate poor sperm morphology and motility, improved sperm parameters can be observed in fluid from a more proximal portion of that epididymis. Even in those epididymides which demonstrated no motile sperm in the caput epididymis, it is possible that motile sperm might have been observed in the more proximal vasa efferentia. These observations have prompted us to inspect the fluid emanating from the transected epididymal tubules during vasoepididymostomy to identify the presence and motility of sperm. When whole motile sperm are identified, vasoepididymostomy is performed at that level. When vasovasostomy has been performed on the contralateral side, or when the opposite side is not available for anastomosis, it was our custom in the past to perform a vasoepididymostomy without identifying motile sperm.
337
Since animal and human studies have shown a positive correlation between fertility rate and the distance from the vasa efferentia to the level of vasoepididymostomy, sacrificing extra length of epididymis to identify motile sperm remains an issue of discussion.1,5-7J2 SilberlO reported on 5 patients who underwent bilateral vasoepididymostomy to the caput epididymis. Initial sperm analysis showed O-l percent motility, but by 1.5 years 4 of 5 had normal sperm motility, Further studies showed significant fertility rates could be achieved with vasoepididymostomy to the caput epididymis (31% ) . l2 The fertility rate correlated well with the sperm motility on follow-up postoperative semen analyses; those with motility less than 20 percent had a fertility rate of 15 percent, while those with motility more than 20 percent had a fertility rate of 58 percent. Significant time (up to 2 years) was required to regain these sperm motilities, and in some of our patients it has taken greater than one year to observe the return of normal sperm counts and motility. In our group of 30 men who underwent vasoepididymostomy only, 21 had non-motile sperm (whole sperm or sperm parts) identified in the epididymal fluid at the time of the procedure. Of the 15 men who had a semen analysis performed at least three months following the procedure, 6 were noted to have normal sperm count. The level of vasoepididymostomy in these 6 patients was to the caput in 1, the corpus in 1, and the cauda in 4, while the epididymal fluid at the time of vasoepididymostomy showed whole but non-motile sperm in 4 of these patients, and sperm parts in 2. Postoperative sperm motility was regained in 5 of 6 (80 %), and 3 of 6 had motility more than 20 percent. There have been three term pregnancies induced by these men, and all three were noted to have whole but non-motile sperm identified in the epididymal fluid at the time of vasoepididymostomy. Thus the return of sperm motility can be observed when vasoepididymostomy is performed at any level of the epididymis and when whole but non-motile sperm or sperm parts are identified in the epididymal fluid at the time of the procedure. However, in our relatively small series, fertilizing ability has been documented only when whole motile or non-motile sperm, rather than sperm parts, are observed in the epididymal fluid. From these retrospective observations, our data suggest that sperm motility may be achieved within or proximal to the caput epi-
338
didymis in both obstructed and nonobstructed epididymides. The fact that normal sperm counts, motility, and subsequent pregnancy were obtained following vasoepididymostomy to an epididymal tubule where the sperm were whole but non-motile, implies that it may not be necessary to identify motile sperm in the epididymal fluid prior to vasoepididymostomy. Although further studies are needed to discern the epididymal level and epididymal fluid characteristics which optimize the chance for in vivo fertilization, our data suggest that in the performance of a vasoepididymostomy, the level of the epididymis which should be selected is the level which contains whole sperm, regardless of their motility, even if this requires incising into the most proximal portion of the epididymis. Los Angeles, California 90024 (DR. WOLFSON) References 1. Bedford JM: Development of the fertilizing ability of spermatozoa in the epididymis of the rabbit, J Exp Zoo1 163: 319 (1966). 2. Bedford JM: The maturation of spermatozoa in the human epididymis, J keprod Fertil (Suppl) 18: 199 (1973). 3. Gaddum I’. and Glover T: Some reactions of rabbit soermatozoa to ligation’of the epididymis, J Reprod Fertil9: 119 11965). 4. Gaddum P: Sperm maturation in the male reproductive tract: development of motility, Anat Ret 161: 471 (1968). 5. Horan AH, and Bedford JM: Development of the fertilizing ability of the spermatozoa in the epididymis of the Syrian hamster, J Reprod Fertil 30: 417 (1972). 6. Orgebin-Christ MC: Studies on the function of the epididymis, Biol Reprod (Suppl) 1: 155 (1972). 7. Paufler SK, and Foote RH: Morphology, motility, and fertility of spermatozoa recovered from different areas of ligated rabbit epididymides, J Reprod Fertil 17: 125 (1968). 8. Schoysman RJ, and Bedford JM: The role of the human epididymis in sperm maturation and sperm storage as reflected in the consequences of epididymovasostomy, Fertil Steri146: 293 (1986). 9. Young WC: A study of the function of the epididymis. III. Functional changes undergone by spermatozoa during their passage through the epididymis and vas deferens in the guinea pig, J Exp Biol 8: 151 (1931). 10. Silber SJ: Vasoepididymostomy to the head of the epididymis: recovery of normal spermatozoa1 motility, Fertil Steril 34: 149 (1980). 11. Silber SJ: Pregnancy with sperm aspiration from the proximal head of the epididymis: a new treatment for congenital absence of the vas deferens, Fertil Steril 50: 525 (1988). 12. Silber SJ: Results of microsurgical vasoepididymostomy: role of epididymis in sperm maturation, Hum Reprod 4: 298 (1989). 13. Silber SJ: Apparent fertility of human spermatozoa from the caput epididymis, J Androl 10: 263 (1989). 14. Silber SJ: Pregnancy caused by sperm from vasa efferentia, Fertil Steril 49: 373 (1988). 15. Wyker R, and Howards SS: Micropuncture studies of the motility of rete testis and epididymal spermatozoa, Fertil Steril 28: 108 (1977). 16. Jequier AM, et al: A pregnancy achieved using sperm from the epididymal caput in idiopathic obstructive azoospermia, Fertil Steril 53: 1104 (1990). 17. Silber SJ: Microscopic vasoepididymostomy: specific microanastomosis to the epididymal tubule, Fertil Steril 30: 565 (1978).
UROLOGY
I
OCTOBER
1992
I
VOLUME 40, NUMBER 4