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S J Silber

Publications and source records attributed to S J Silber.

At least 19 recordsLinked to original sources
PubMed1992

Testicular origin of immunobead-reacting antigens in human sperm.

OBJECTIVE: To investigate, by means of immunobinding technique, the antigenic surface expression of human vasa efferentia sperm as compared with that of ejaculated sperm. DESIGN: Briefly, vasa efferentia sperm, retrieved microsurgically, and donors' ejaculated sperm (controls) were used. PATIENTS, PARTICIPANTS: Men with congenital absence of the vas deferens, undergoing sperm aspiration as part of their infertility treatment, and controls who were donors of our sperm bank were first assayed by direct immunobead test and, if found negative, were exposed to sera containing known high titers of antisperm antibodies and then retested by indirect immunobead test. RESULTS: The data showed no difference in binding titers and class of immunoglobulins between vasa efferentia and ejaculated sperm. CONCLUSIONS: These findings suggest that, in humans, sperm acquire those surface antigens commonly detected by immunobinding test within the testes before their transit through the epididymis.

Epididymis↗
PubMed1992

The role of the laboratory in the handling of epididymal sperm for assisted reproductive technologies.

This report describes the historical experience of our laboratory in the handling and processing of epididymal sperm from men with congenital absence of the vas deferens. Three different methods of sperm preparation were used: swim-up or resuspension in the first group of patients treated, mini-Percoll in the second group, and mini-Percoll used in conjunction with pentoxifylline and 2' deoxyadenosine in the third group. Twenty-four percent of cases achieved fertilization in group I, whereas in groups II and III the rate was 59% and 57%, respectively. Fertilization rates in each group were 6.5% in group I, 16% in group II, and 35% in group III. Three pregnancies were obtained in group I, 13 in group II, and 2 in group III. Groups II (21%) and III (63%) were able to have excess embryos to cryopreserve.

Epididymis↗
PubMed1992

Ultrastructure of human sperm in men with congenital absence of the vas deferens: clinical implications.

OBJECTIVE: To determine the ultrastructural features of epididymal and vasa efferentia sperm in men with congenital absence of the vas deferens. DESIGN: Prospective. SETTING: University of California Irvine Center for Reproductive Health. PATIENTS: Thirteen men with surgical diagnosis of congenital absence of the vas deferens undergoing epididymal and vasa efferentia aspiration for assisted reproductive technology procedures. RESULTS: The morphological quality and the integrity of the spermatozoa aspirated from the extratesticular segment of the rete testis, the vasa efferentia, and the caput epididymis were always markedly superior to those of sperm aspirated from the corpus and cauda epididymis, where the vast majority, if not all, were degenerating or frankly necrotic. The aspirates obtained from the distal segments of the epididymis also contained large numbers of sperm-laden macrophages; these were instead absent or exceptional in the fluids aspirated from the pre-epididymal portions of the excurrent pathways and from the caput of the epididymis. CONCLUSIONS: This study demonstrates that the ultrastructural morphology of spermatozoa obtained by aspiration from the rete testis, vasa efferentia, and caput epididymis of individuals with congenital absence of the vas deferens is indistinguishable from that of spermatozoa in the semen.

Congenital Abnormalities↗
PubMed1992

Penetration of zona-free hamster oocytes using human sperm aspirated from the epididymis of men with congenital absence of the vas deferens: comparison with human in vitro fertilization.

OBJECTIVES: To assess the ability of sperm aspirated from the epididymis of men with congenital absence of the vas deferens to penetrate zona-free hamster oocytes. To directly compare the performance of human epididymal sperm in the zona-free hamster oocyte sperm penetration assay (SPA) with the results of human in vitro fertilization (IVF). DESIGN: Sperm penetration assay was carried out with epididymal sperm retrieved microsurgically, and with ejaculated sperm obtained from fertile donors (internal controls). For direct comparison, SPA was performed with the same epididymal sperm sample used for IVF. PATIENTS, PARTICIPANTS: Men with congenital absence of the vas deferens undergoing sperm aspiration as part of their infertility treatment and control donors who provided ejaculated sperm. RESULTS: Epididymal sperm penetrated SPA with a score of 0% to 30%. The SPA scores for internal controls using ejaculated sperm was 30% to 71%. Linear regression analysis of the association between penetration scores in SPA and fertilization rate in IVF indicated a positive correlation that was highly significative. CONCLUSIONS: These findings using SPA confirm previous reports on the fertilizing potential of human epididymal sperm and its ability to produce normal pregnancies. The good correlation between SPA and human IVF using epididymal sperm suggest that SPA is an excellent bioassay to test laboratory experimental conditions for improving fertilizing capacity of human epididymal sperm.

Adult↗
PubMed1992

Relationship of epididymal sperm antibodies to their in vitro fertilization capacity in men with congenital absence of the vas deferens.

OBJECTIVES: To test, using the immunobead binding technique, for the presence of antisperm antibodies on epididymal sperm, in epididymal fluid, and in serum of men with congenital absence of the vas deferens. To evaluate the in vitro fertilization (IVF) capacity of human epididymal sperm in the presence of antisperm antibodies. DESIGN: Prospective. At the time of oocyte insemination, sperm from the proximal caput epididymis or vasa efferentia were tested by direct immunobinding technique. The epididymal fluid and serum were tested by indirect immunobinding technique. SETTING: Center for Reproductive Health, University of California-Irvine. PATIENTS: Forty-five patients with congenital absence of the vas deferens participating in the microsurgical epididymal sperm aspiration and IVF program. MAIN OUTCOME MEASURE: Incidence of antisperm antibodies to epididymal sperm and their relationship with IVF results. RESULTS: Sixteen men (35%) tested positively to the direct immunobead test on epididymal sperm; 7 (16%) were positive in epididymal fluid and 13 (29%) were positive in serum. Five pregnancies (31%) occurred in the positive group of which two were from patients who had sperm binding of 100% for immunoglobulin (Ig)G (all over sperm surface) and 90% (midpiece, tail) and 50% (tail, tiptail), respectively, for IgA. Five pregnancies (18%) were obtained in the negative group. No statistical difference was observed in the overall fertilization rate between the two groups. CONCLUSION: Human epididymal sperm and epididymal fluid retrieved from men with congenital absence of the vas deferens can react positively to immunobead test. However, the presence of antisperm antibodies do not seem to impair the IVF capacity of epididymal sperm.

Autoantibodies↗
PubMed1991

Movement characteristics of human epididymal sperm used for fertilization of human oocytes in vitro.

STUDY OBJECTIVE: To develop mathematical models using kinematic parameters from Computer-Aided Sperm Analysis (CASA) that predict the fertilization rate of sperm recovered from the caput epididymidis and to test the hypothesis that fertilization was enhanced by the presence of specific sperm subpopulations in the inseminate. SETTING: In vitro fertilization (IVF) program. PATIENTS: Thirteen patients with congenital absence of the vas deferens provided epididymal sperm for IVF as well as for CASA. RESULTS: The mathematical model that was most predictive of fertilization rates included kinematic parameters of the epididymal aspirate (percent motility), the inseminate used for IVF (curvilinear velocity [VCL]), and the change in sperm movement after in vitro processing by the mini-Percoll technique (difference in amplitude of lateral head displacement [ALH]). Multivariate cluster analysis revealed that inseminates that resulted in higher fertilization rates had subpopulations of sperm that were characterized by high VCL and high mean angular displacement, as well as a greater change in ALH after processing. CONCLUSION: In vitro fertilization with epididymal sperm was more likely to succeed when the sperm population that was initially aspirated had a higher proportion of motile cells and when these sperm were capable of capacitation in vitro as indicated by the appearance of sperm subpopulations with motility that resembled hyperactivation.

Diagnosis, Computer-Assisted↗
PubMed1991

When predictions don't predict.

One of the most widespread abuses of statistical methods involves the misinterpretation of statistical significance after the application of multiple comparisons. This paper highlights the problem by demonstrating 'significance' when clearly none exists.

Female↗
PubMed1990

Congenital absence of the vas deferens. The fertilizing capacity of human epididymal sperm.

BACKGROUND: Congenital absence of the vas deferens has been considered a virtually untreatable cause of male sterility. Furthermore, sperm that have not passed through at least the head of the epididymis have been thought to be incapable of causing pregnancy. We attempted to determine whether human sperm that had never passed through the epididymis could fertilize eggs in vitro and whether the technique could be used for men with congenital absence of the vas deferens. METHODS: Twenty-eight men with congenital absence of the vas deferens underwent microsurgical aspiration of sperm from the epididymis and vasa efferentia for attempted in vitro fertilization of their wives' oocytes, with subsequent transfer of embryos. Thirty-two treatment cycles were begun (four were repeat cycles). RESULTS: The most motile sperm were found in the proximal epididymis, at or near the vasa efferentia. Embryos were obtained for transfer in 21 cases (66 percent). Ninety-three embryos resulted from 352 mature oocytes (fertilization rate, 26 percent). Clinical pregnancy was achieved in 10 of the 32 treatment cycles (31 percent). Seven women delivered normal infants, and three miscarried. One of the seven live births was of twins. There were six girls and two boys. When fewer than 10 eggs were retrieved, no pregnancy occurred. When 10 or more eggs were retrieved (20 cases), the pregnancy rate was 50 percent. CONCLUSIONS: Sperm from the proximal caput epididymidis and even sperm from the vasa efferentia (which have never passed through the epididymis) can fertilize the human oocyte in vitro and result in pregnancy with live birth.

Adult↗
PubMed1990

Quantitative evaluation of spermatogenesis by testicular histology in men with congenital absence of the vas deferens undergoing epididymal sperm aspiration.

A quantitative histological evaluation of testicular biopsy in patients undergoing microsurgical epididymal sperm retrieval for in-vitro fertilization revealed no correlation between the quantity or quality of spermatozoa retrieved and the actual testicular sperm production. Poor retrieval of sperm was associated with blockage induced by secondary pressure damage in the rete testis collecting area.

Biopsy, Needle↗
PubMed1989

Role of epididymis in sperm maturation.

One hundred ninety patients with obstructive azoospermia caused by bilateral epididymal blockage have been followed up for four years or longer after undergoing "specific tubule" vasoepididymostomy. When anastomosis was required in the corpus epididymis, the "patency" rate was 78 percent, and the overall pregnancy rate was 56 percent. The pregnancy rate for "patent" cases was 72 percent, indicating that a high fertility rate can be obtained with sperm that have not transited the full length of corpus epididymis. By contrast, with vasoepididymostomy to the caput epididymis there was a 73 percent "patency" rate, but the overall pregnancy rate was only 31 percent. The pregnancy rate for "patent" cases was 43 percent. Sperm from the corpus epididymis have a higher rate of fertility than sperm from the caput epididymis, but sperm from proximal areas of the corpus have no less fertility than sperm from the distal corpus epididymis. The most remarkable observation is that in almost half the cases sperm that have never journeyed beyond the caput epididymis seem to be capable of causing pregnancy.

Anastomosis, Surgical↗
PubMed1989

Results of microsurgical vasoepididymostomy: role of epididymis in sperm maturation.

One-hundred-and-ninety patients with obstructive azoospermia caused by bilateral epididymal blockage have been followed for greater than or equal to 4 years after undergoing 'specific tubule' vasoepididymostomy. When anastomosis was required in the corpus epididymidis, the 'patency' rate was 78% and the overall pregnancy rate was 56%. The pregnancy rate for 'patent' cases was 72%, indicating that a high fertility rate can be obtained with spermatozoa that have not passed through the full length of corpus epididymidis. By contrast, with vasoepididymostomy to the caput epididymidis there was a 73% 'patency' rate, but the overall pregnancy rate was only 31%. The pregnancy rate for 'patent' cases was 43%. Spermatozoa from the corpus epididymidis have a higher rate of fertility than spermatozoa from the caput epididymidis, but spermatozoa from proximal areas of the corpus have no less fertility than spermatozoa from the distal corpus epididymidis. The most remarkable observation is that in almost half the cases, spermatozoa which have never journeyed beyond the caput epididymidis seem to be capable of causing pregnancy.

Epididymis↗
PubMed1989

Pregnancy after vasovasostomy for vasectomy reversal: a study of factors affecting long-term return of fertility in 282 patients followed for 10 years.

The aim of this study was to determine the eventual fertility of those patients following vasectomy reversal who have no pressure-induced secondary epididymal blockage. These patients underwent simple vasovasostomy because at the time of the reversal surgery there were sperm present in large numbers in the vas fluid. It was possible to obtain long-term follow-up on 326 early patients who underwent vasectomy reversal 8-10 years ago. Two hundred and eighty-two of those patients had sperm in the vas fluid. These patients were studied for pregnancy rate and post-operative semen parameters in relation to presence or absence of sperm in the vas fluid at the time of vasectomy reversal, duration of time since vasectomy, pre-operative serum antisperm antibody titers, the influence of varicocoele and quantitative evaluation of testicular biopsy. All of the 44 patients with no sperm in the vas fluid remained azoospermic following vasovasostomy. Of the 282 patients with sperm in the vas fluid, 228 (81%) eventually impregnated their wives. Twenty-four patients with sperm in the vas fluid (9%) were azoospermic and did not impregnate their wives. Of the 258 patients who had sperm patency, the pregnancy rate was 88%. The number of mature spermatids per tubule in the testis correlated closely with the post-operative sperm count in patent cases. Quantitative evaluation of the testicular biopsy revealed normal spermatogenesis, even in patients with azoospermia or severe oligospermia post-operatively. Technical failures were due to blockage either at the vasovasostomy site, or epididymal blockage unrecognized at the time of vasovasostomy.2+perm count had a minimal impact on the

Female↗
PubMed1989

Programming of ovarian stimulation with norethindrone acetate in IVF/GIFT cycles.

Twenty patients were given norethindrone acetate (NET) to program the initiation of controlled ovarian hyperstimulation and to coordinate follicular aspiration with surgery to obtain spermatozoa from the husband. Patients received NET, 10 mg/day orally, starting between days 2 and 4 of the cycle. The duration of NET therapy varied from 9 to 37 days. The mean time of onset of vaginal bleeding, after cessation of NET, was 2.9 +/- 0.7 days. Ovarian stimulation was carried out with a combination of a luteinizing hormone releasing hormone analog, follicle-stimulating hormone and human menopausal gonadotrophin. The day of human chorionic gonadotrophin (HCG) administration ranged from day 8 to day 15 of the cycle (10.1 +/- 1.7). On the day of HCG injection, the mean E2 level was 2188 +/- 1126. The mean number of follicles aspirated was 18.4 +/- 9.9 per cycle. The mean number of oocytes collected per cycle was 15.5 +/- 8.5. There was no correlation between duration of NET suppression and the number of days of gonadotrophin therapy needed to reach HCG administration. The large number of oocytes retrieved is probably related more with the fact that the patients represented a group with a purely male factor of infertility, than by the specific drug protocol utilized. Our results demonstrate that the ovarian response to gonadotrophin stimulation was not affected by NET administration. The main advantages of the use of this drug for cycle control are that its administration is oral, simple and inexpensive.

Adult↗
PubMed1989

The relationship of abnormal semen parameters to male fertility.

To what extent do standard semen parameters reflect male fertility? A review of many studies over the last 35 years relating pregnancy rate to sperm counts in 'fertile' and 'infertile' couples indicates that standard semen parameters, though much maligned of late, are useful in evaluating the degree of 'male factor' in an infertile couple. However, 'male factor' is quite compatible with fertility in a couple if the wife is very fertile. Oligoasthenozoospermia is, unfortunately, for the most part, an untreatable condition. Yet, vigorous treatment of the wife may still result in pregnancy despite very poor semen quality. Higher sperm counts in an infertile couple are associated with higher pregnancy rates. But in the majority of infertile couples in whom the sperm count is poor, female factors also exist that prevent conception. If the wife were very fertile, she would have become pregnant despite her husband's oligozoospermia, and they would never have seen a physician for infertility. Thus, pregnancy can be achieved with very low sperm counts either by treatment of the wife, IVF, GIFT or ZIFT procedures.

Female↗