Clinical experience and applications of oocyte cryopreservation

Oocyte cryopreservation is a viable solution for the ethical problems related to embryo storage, and the only available technique for preservation of fertility in women who have to undergo chemo- or radiotherapy. The main problems with oocyte cryopreservation are concerned with the survival rate and the fertilization rate. Recently the introduction of the intracytoplasmic sperm injection (ICSI) led to an increase in the fertilization rate. The success achieved with the first case treated encouraged us to set up a clinical trial on human oocyte cryopreservation. In the first stage of the study, 23 women with tubal infertility were enrolled. Superovulation was induced and 375 oocytes were retrieved; of these 338 oocytes were frozen. The survival rate was 59.5% and was independant of the duration of cryopreservation or the presence of cumulus. The normal fertilization rate was 64.4%, and only 7.5% of fertilizations were abnormal. A total of 90.8% of fertilized oocytes cleaved. A mean of 3.1+/-1.3 embryos per patient were transferred. Three pregnancies were achieved. In the second stage of our investigation, more patients were enrolled and similar results were observed. Sixteen pregnancies were achieved. A further stage of the investigation involved the fertilization of frozen oocytes with frozen sperm and even these resulted in a pregnancy. Our study demonstrated that pregnancies can also be achieved when frozen eggs are fertilized by testicular and epididymal sperm. As a consequence of the success of our investigations, a program of oocyte cryopreservation for oncological patients has been initiated in our centre. In our opinion, oocyte cryopreservation is, at present, a safe and efficient technique as documented by the birth of several healthy children.     

Intracytoplasmic sperm injection with cryopreserved testicular spermatozoa

To assess if testicular sperm cryopreservation is a valid alternative to repetition of testicular sperm retrieval techniques, results of a cryopreservation technique in pills have been retrospectively analyzed. Enough motile spermatozoa for ICSI were obtained in 172 from 190 (90.5%) frozen-thawed testicular sperm samples. Overall, 249 couples underwent 390 ICSI cycles, 156 using fresh and 234 using cryopreserved testicular sperm. Mean two-pronuclear fertilization rates per cycle were not significantly different after ICSI with fresh (62.0%) or with cryopreserved (63.2%) spermatozoa. Mean embryo cleavage rate per cycle was higher in the fresh (90.6%) than in the cryopreserved (84.6%) group (P = 0.016). However, clinical pregnancy rates per cycle (28.2% with fresh vs 27.8% with cryopreserved), implantation rates (12.2% vs 13.1%) and ongoing pregnancy rates per cycle (22.4% vs 21.8%) were not significantly different. Cryopreservation of testicular spermatozoa is an effective technique that can be used both in obstructive and in non-obstructive azoospermia.     

Cryopreserved and frozen hyaline cartilage imaged by environmental scanning electron microscope. An experimental and prospective study

OBJECTIVE: To obtain images of the articular surface of osteochondral grafts (fresh, frozen, and cryopreserved in RPMI) using an environmental scanning electron microscope (ESEM). To evaluate and compare the main morphological aspects of the chondral surface of the fresh, frozen, and cryopreserved grafts as visualized via ESEM. METHODS: The study was based on osteochondral fragments from the internal condyle of the knee joint of New Zealand rabbits, corresponding to the chondral surface from fresh, frozen, and cryopreserved samples. One hundred ESEM images were obtained from each group and then classified according to a validated system. The kappa index and the corresponding concordance index were calculated, and the groups were compared by Pearson's chi-squared test (p < 0.05). RESULTS: The articular surface of cryopreserved osteochondral grafts had fewer even surfaces and filled lacunae and a higher number of empty lacunae as compared to fresh samples; these differences correspond to images of cell membrane lesions that lead to destruction of the chondrocyte. Frozen grafts showed more hillocky and knobby surfaces than did fresh grafts; they also had a greater number of empty chondrocyte lacunae. CONCLUSION: ESEM is useful for obtaining images of the surface of osteochondral grafts. When compared to fresh samples, cryopreservation in RPMI medium produces changes in the surface of hyaline cartilage, but to a lesser extent than those produced by freezing.     

Cryopreservation of testicular tissue

Cryopreservation of testicular tissue might benefit prepubertal boys who have to undergo chemotherapy or radiotherapy. Cryopreservation of testicular tissue is feasible. Live offspring have been born to mice, but not other species after transplantation of testicular cells. Spermatogenesis in vitro would be an excellent option for boys with leukaemia, but the method is not feasible for the time being. Cryopreservation of biopsied testicular tissue for intracytoplasmic sperm injection (ICSI) is a feasible option for infertility treatment of azoospermic men. Testicular sperm can be frozen as cell suspension, or within a piece of testicular tissue. Both methods result in pregnancies. Testicular needle biopsy is a simple method to obtain tissue for histological diagnosis, for ICSI and for cryopreservation for use in the future. Testicular sperm should be cryopreserved whenever a testicular biopsy is carried out.     

Frozen pronuclear oocytes: advantages for the patient

Since the first reported pregnancy in a human being after a frozen/thawed eight cell stage preembryo, cryopreservation of preembryos has been integrated as an important element of assisted reproductive technologies (ART). The cryopreservation technique has brought several advantages to ART. It allows the transfer of a limited number of embryos in the collection cycle, thereby reducing the risk of multiple pregnancies, and the patients have a reservoir of excess embryos for additional transfers. This maximises the number of embryo transfers per oocyte retrieval, while at the same time increasing the cumulative pregnancy rate from a given treatment cycle. Also, the ability to freeze all the embryos obtained and transfer at a subsequent cycle is useful in the avoidance of hyperstimulation syndrome, or when factors that may jeopardize implantation are apparent. Freezing of oocytes in a pronuclear stage has a valuable role in the management of infertility. Supernumerary zygotes can be cryopreserved safely for future transfer, avoiding additional inconvenience for the patients. The freezing thawing technique does not have any adverse effects on oocytes fertilized microsurgically. Pronuclear stage oocytes eventually survive the cryopreservation procedure better, yielding after culture cleaved embryos appropriate for transfer, which could increase the implantation rate. We believe that the cryopreservation of cleaved embryos, which is problematic, can be safely replaced by this procedure. This is not only an advantage for society as a whole, but also for the people involved in the process, as there should be no ethical or moral conflict for the patients or for the laboratory staff about discarding this material.     

Effects of cryopreservation on meiotic spindles of oocytes and its dynamics after thawing: clinical implications in oocyte freezing--a review article

Embryo freezing has been a successful practice, but oocyte cryopreservation formerly achieved poorer results. This was mainly due to low rates of survival, fertilization, and development. The major dissimilarities for oocytes to embryos are the character of the plasma membrane, the presence of cortical granules, at the metaphase of meiosis II with the spindle system. In addition, the oocytes must be fertilized by sperm at the appropriate time. To improve the survival rate, a refined slow freezing method with increased sucrose concentration would dehydrate oocytes more sufficiently. Vitrification is another approach to prevent ice crystal formation. Intracytoplasmic sperm injection is used to overcome possible zona hardening from the release of cortical granules. The microtubules of meiotic spindles are vulnerable to the thermal changes and would depolymerize. Cryopreserved oocytes exhibited serious disturbances of the microtubules immediately after thawing. Fertilization of oocytes with disorganized spindles could lead to chromosomal aneuploidy, digyny, and arrest of cleavage. After incubation, the microtubules would repolymerize in a time-dependent way. Normal fertilization and development of cryopreserved oocytes improved after appropriate incubation and timing of insemination, compatible with recovery of the spindles. With the improvement of survival, fertilization, and cleavage, oocyte cryopreservation would gain an imperative role.     

Feasibility of microsurgical reconstruction of the male reproductive tract after percutaneous epididymal sperm aspiration (PESA)

For obstructive azoospermia, surgical sperm retrieval from the epididymis for IVF/ICSI is an established management. However, various recent studies have established that surgical reconstruction with vasovasostomy or vasoepididymostomy remains a more cost-effective treatment option than upfront assisted reproduction. After epididymal sperm retrieval, fibrosis and scarring of the punctured epididymal tubule can lead to complete epididymal obstruction. The feasibility of surgical reconstruction after surgical epididymal sperm retrieval has not been established. We describe two cases of bilateral microsurgical vasoepididymostomy, using a new 2-suture longitudinal intussusception technique we previously described, after previous successful bilateral percutaneous epididymal sperm aspiration (PESA). In both cases, motile sperm were found in ejaculate in the first post-operative semen analysis at 6 weeks and 2 months. We conclude that even in men with previous epididymal sperm retrieval, surgical reconstruction remains a feasible management option for fertility.     

Evaluation of the clinical efficacy of embryo cryopreservation

To fully evaluate the advantages of a cryopreservation program a method needs to be established to express the additional patients pregnant from cryopreservation. The patient specific method considers cryopreservation as augmentation only among patients without a pregnancy from the fresh transfer, or from previously transferred frozen material from the same harvest. In an analysis of the pregnancy rate at the Jones Institute between January 1996 and December 1998 we found a fresh pregnancy rate of 40.8% in the good responders and 28.8% in poor responders. The patient specific pregnancy rate in the same cycles was 53.4% in good responders and 32.3% in poor responders. Good responders less than 35 years of age with ten or more mature eggs at retrieval had a fresh pregnancy rate of 40.2% and a patient specific pregnancy rate of 57.9%. It is exceedingly important for the physician and patient to understand and comprehend the potential in cryopreserved material.     

Success of testicular sperm extraction [corrected] and intracytoplasmic sperm injection in men with Klinefelter syndrome

PURPOSE: The aim of this study was to report the successful fertility treatment of men with Klinefelter syndrome using testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). METHODS: A total of 42 men with Klinefelter syndrome who underwent 54 TESE procedures were identified. Before TESE, patients with serum testosterone levels less than 15.6 nmol/liter were treated with an aromatase inhibitor. Sperm retrieval rates and results of ICSI, including fertilization and clinical pregnancy, were collected. RESULTS: Mean pretreatment FSH and testosterone levels were 33.2 IU/liter and 9.8 nmol/liter. During medical therapy, the mean testosterone level rose to 17.0 nmol/liter (P < 0.01). Spermatozoa were found during 39 microdissection TESE procedures, on the day before, or day of oocyte retrieval during a programmed in vitro fertilization cycle. The sperm retrieval rate was 72% (39 of 54) per TESE attempt, and 29 of the 42 different men (69%) had adequate sperm found for ICSI. Thirty-three in vitro fertilization cycles yielded embryos for transfer in the 39 (85%) cycles with sperm retrieved. Eighteen clinical pregnancies have resulted in 21 live births [18 of 39 (46%)]. All children had a normal karyotype. CONCLUSION: TESE/ICSI is a successful intervention for the majority of patients with azoospermia and Klinefelter syndrome. Sperm retrieval and ICSI success in men with Klinefelter syndrome are comparable with other men with nonobstructive azoospermia treated at our center.     

ICSI outcomes of fresh or cryopreserved spermatozoa from micro-TESE in patients with nonobstructive azoospermia: CONSORT

The aim of this study was to evaluate intracytoplasmic sperm injection (ICSI) outcomes of fresh and cryopreserved sperm via microdissection testicular sperm extraction (micro-TESE) in patients with nonobstructive azoospermia (NOA).From March 2016 to February 2020, a total of 244 men with NOA underwent micro-TESE at the Center for Reproductive Medicine, First Hospital of Jilin University, P. R. China. These cases included 40 patients who underwent 40 ICSI cycles with fresh spermatozoa from micro-TESE (Group A) and 30 patients who underwent 30 ICSI cycles with cryopreserved spermatozoa from micro-TESE (Group B). The characteristics, embryonic development, and ICSI outcomes of patients were compared between groups A and B.Our sperm retrieval rate (SRR) by micro-TESE in patients with NOA was 35.25%. No statistical differences in the patient characteristics and fertilization or quality embryo rates were observed between Groups A and B. Higher miscarriage rates and lower live births were observed in Group B than in Group A (both P < .05).Fresh testicular spermatozoa seem to produce better ICSI outcomes than cryopreserved testicular spermatozoa from patients with NOA in the micro-TESE-ICSI cycle.     

The developmental potential of cryopreserved human embryos

Using rigorously matched non-frozen controls we have shown that cryopreservation does not alter the implantation potential of early cleavage stage (day 2) human embryos if no blastomere loss occurs. Thawed intact 4-cell embryos have a significantly higher implantation (fetal heart) rate (16.9%) than similar 2-cell embryos (7.2%). This difference is not due to blastomere number per se since increasing the cell number in frozen embryos by allowing an extended period in culture prior to freezing does not alter their intrinsic developmental potential. Blastomere loss, which occurred in almost half of all thawed embryos, is directly related to a reduction in developmental potential. We estimate that approximately 30% of the expected fresh embryo implantations are lost as a consequence of cryopreservation. Both preimplantation and peri-implantation losses may contribute to this outcome.     

Embryo freezing after intracytoplasmic sperm injection

This study reports on the safety and efficiency of the cryopreservation of human embryos obtained after intracytoplasmic sperm injection. For this, we evaluated the morphological survival, the capacity of the surviving embryo to develop further in vitro and in vivo. After freezing-thawing embryos obtained after ICSI, 40% of the embryos do not survive the cryopreservation procedure. After selective transfer of further cleaving frozen-thawed embryos, pregnancy loss was 31% (subclinical pregnancy rate of 13% and miscarriage rate of 18%). As a result the livebirth rate per transferred embryos and per thawed embryo was 7 and 3% respectively. Obstetric outcome as well as further follow-up of the children born indicate that cryopreservation of ICSI embryos is a safe procedure, long term follow-up of the children born however is still warranted.     

Birth of rhesus monkey infant after in vitro fertilization and nonsurgical embryo transfer.

The birth of a rhesus monkey resulting from in vitro fertilization is reported. Oocytes recovered at laparoscopy from five gonadotropin-stimulated donors were inseminated in vitro with sperm preincubated with caffeine and dibutyryl cyclic AMP. After insemination, oocytes were cultured for 33-46 hr. Twenty-two embryos were transferred nonsurgically into 11 recipient females. One recipient showed signs of implantation but did not carry to term. A second female became pregnant after receiving one 4-cell and one 6-cell embryo fertilized in vitro. The subsequent course of early pregnancy and embryonic and fetal development were characteristic of normal singleton pregnancies. A healthy term male infant was delivered by Cesarean section 176 days after fertilization. This birth has validated our procedures for in vitro fertilization of rhesus monkey gametes and provides an experimental model for studies of early embryonic development in primates.     

Transportation and cryopreservation may impair haematopoietic stem cell function and engraftment of allogeneic PBSCs, but not BM

Recent data suggest that the practice of using frozen allogeneic grafts is becoming increasingly common among transplant centres. Therefore, we retrospectively analysed 31 frozen allogeneic PBSC and 8 BM grafts by flow cytometry with regard to their CD34+ content, membrane integrity (7-AAD) and stem cell-specific enzyme activity (aldehyde dehydrogenase, ALDH) in relation to individual transplantation results. Membrane integrity of CD34+ cells was significantly impaired in cryopreserved PBSC but not in BM compared to unfrozen allografts. In 9 out of 31 frozen PBSC (but none of the BM) grafts numbers of SSC(lo)ALDH(br) cells per kg body weight (BW) were significantly reduced while in the same grafts the numbers of CD34+ cells per kg BW were close to normal. Overall, 9 out of 33 patients (27%) who received unrelated PBSC allografts cryopreserved after transportation did not achieve engraftment. For comparison, primary graft failure was observed in our centre in only 7 out of 493 recipients (1.4%) of fresh allogeneic PBSC grafts. Moreover, we did not see any graft failure in patients receiving frozen/thawed BM or autologous PBSC transplants. We, therefore, conclude that PBSC grafts become much more sensitive to cryopreservation after transport and/or storage. Importantly, the engraftment potential of frozen HSC grafts may reliably be predicted by measuring ALDH activity.     

Cryopreserved mouse hepatocytes retain regenerative capacity in vivo

BACKGROUND & AIMS: Substitution of hepatocyte transplantation for whole liver transplants in selected individuals with liver disease could significantly expand the number of patients to benefit from use of scarce donor livers. However, successful hepatocyte transplantation may require that donor cells retain normal functional and proliferative capabilities and that they be readily available. Banking of cryopreserved hepatocytes would fulfill the latter requirement. Cryopreservation protocols have been developed that minimize hepatocyte injury and allow preservation of metabolic activity. The aim of this study was to assess cryopreserved hepatocyte proliferative capacity in vivo after thawing. METHODS: Fresh and frozen/thawed mouse hepatocytes were transferred separately into the livers of recipient mice with transgene-induced liver disease, an environment that is permissive for clonal expansion of donor cell populations. Fresh and cryopreserved donor cells were compared for their ability to proliferate and replace damaged parenchyma. RESULTS: Although cryopreservation decreased hepatocyte viability, individual viable frozen/thawed hepatocytes demonstrated clonal replicative potential identical to that of fresh hepatocytes. Even after storage for 32 months in liquid nitrogen, transplanted hepatocytes constituting 0.1% of total adult hepatocyte number could repopulate a mean of 32% of recipient liver parenchyma. CONCLUSIONS: These findings suggest that cryopreserved hepatocytes represent an appropriate source of cells for therapeutic hepatocyte transplantation.     

Serum progesterone levels predict success of in vitro fertilization/embryo transfer in patients stimulated with leuprolide acetate and human menopausal gonadotropins

Serum progesterone (P4) levels greater than 2.86 nmol/L (0.9 ng/mL) on the day of hCG administration are reportedly associated with decreased pregnancy rates in in vitro fertilization/embryo transfer (IVF/ET) cycles. To further assess this phenomenon we measured serial serum P4, LH, and estradiol levels in 115 consecutive patients undergoing stimulation for IVF/ET with midluteal leuprolide acetate and human menopausal gonadotropins. IVF/ET cycle outcome was retrospectively correlated with P4 levels on the day of hCG administration. Two critical breakpoints were identified, 1.27 nmol/L (0.4 ng/mL) and 286 nmol/L (0.9 ng/mL). Clinical pregnancies occurred in 9 of 18 patients in group I (P4, less than 1.27 nmol/L) compared to 11 of 81 patients in group II (1.27 less than P4 less than 2.86 nmol/L; P = 0.001) and 0 of 14 patients in group III (P4, less than or equal to 2.86 nmol/L) (P = 0.001). Eleven patients in group III had cryopreservation of embryos during that cycle. Six subsequently underwent frozen embryo transfer, and clinical pregnancies occurred in 2, both of whom have delivered. These findings demonstrate that even modest increases in serum P4 levels (greater than 1.27 nmol/L) are associated with reduced pregnancy rates in IVF/ET cycles. In addition, it appears that the mechanism may not exclusively involve poor oocyte quality.     

Coculture of human embryos with autologous human endometrial epithelial cells in patients with implantation failure.

We have developed a coculture system with autologous human endometrial epithelial cells (AEEC) that retained many features of human endometrial epithelium. Implantation failure (IF; >3 previous cycles failed with 3-4 good quality embryos transferred) is a distressing condition in which 2-day embryo transfer repetition is the routine option. The objective of this study was to investigate the basics and to evaluate prospectively the clinical value of embryo coculture on AEEC and blastocyst transfer with their own oocytes [in vitro fertilization (IVF) patients] or with donated oocytes (oocyte donation patients) compared to a routine day 2 embryo transfer for patients with IF. Scanning electron microscopy and mouse embryo assays demonstrate that EEC from fertile and IF patients were morphologically and functionally similar; similar findings were observed in EEC obtained from fresh or frozen endometria. Clinically, 168 IVF cycles were performed in 127 patients with 3.8+/-0.2 previously failed cycles, and 80 cycles were performed in 57 patients undergoing oocyte donation with 3.0+/-0.2 previously failed cycles. Twenty IVF patients and 15 ovum donation patients with 3 previously failed cycles in whom a 2-day embryo transfer was performed were used as controls. In 88% of ovum donation cycles, at least 2 blastocysts were available for transfer, with 60.1% blastocyst formation; 2.2+/-0.1 blastocysts were transferred/cycle, and 36 pregnancies (determined by fetal cardiac activity) were obtained (32.7% implantation and 54.5% pregnancy rates). In 168 IVF cycles, 8.1+/-0.2 embryos/cycle started coculture, resulting in 49.2% blastocyst formation; 2.3+/-0.2 blastocysts were transferred/cycle, and 29 clinical pregnancies were obtained (11.8% implantation and 20.2% pregnancy rates). Fifteen cycles were canceled (9%). In oocyte donation patients with IF undergoing 2-day embryo transfer, implantation and pregnancy rates were significantly lower (4.5% and 13.3%; P < 0.01) than with coculture; however, in IVF patients with IF, results with day 2 transfer (10.7% and 35%) were similar to those with coculture. The present study demonstrates that coculture of human embryos with AEEC and blastocyst transfer is safe, ethical, and effective and constitutes a new approach to improve implantation in patients with IF undergoing ovum donation, but not in IVF patients.     

Autologous survival of cyanate-treated cryopreserved sickle erythrocytes

The effects of carbamylation and frozen storage on the autologous 51Cr survival and metabolic features of sickle erythrocytes (S-RBCs) were determined. Red cells from four patients with sickle hemoglobinopathies were treated with 50 mM sodium cyanate for 2 hr (37 degrees C), glycerolized and frozen (-80 degrees C) for 62-153 days. The mean in vitro loss of S-RBCs from the combination of cyanate treatment and cryopreservation was 23.6% ( +/- 3.5 SD). The 2,3-diphosphoglycerate content of the thawed cells did not change significantly. However, ATP levels decreased to about 50% of the corresponding values in fresh, untreated S-RBCs. Despite this decrease in ATP, the mean intravascular survival of the frozen cyanated cells nearly doubled. At the high concentration of cyanate used, the oxygen affinity of S-RBCs increased markedly: Their mean P50 was 13.1 mm Hg ( +/- 1.9SD). The gelation of HbS at zero pO2 was also markedly inhibited in the one sample of cyanate-treated S-RBCs examined. Clinical studies to determine the efficacy of autologous transfusions with extensively carbamylated, cryopreserved S-RBCs should be considered.     

Safety and efficacy of sperm washing in HIV-1-serodiscordant couples where the male is infected: results from the European CREAThE network

OBJECTIVE: To examine the safety and effectiveness of assisted reproduction using sperm washing for HIV-1-serodiscordant couples wishing to procreate where the male partner is infected. DESIGN AND METHODS: A retrospective multicentre study at eight centres adhering on the European network CREAThE and involving 1036 serodiscordant couples wishing to procreate. Sperm washing was used to obtain motile spermatozoa for 3390 assisted reproduction cycles (2840 intrauterine inseminations, 107 in-vitro fertilizations, 394 intra-cytoplasmic sperm injections and 49 frozen embryo transfers). An HIV test was performed in female partners at least 6 months after assisted reproduction attempt. The outcome measures recorded were number of assisted reproduction cycles, pregnancy outcome and HIV test on women post-treatment. RESULTS: A total of 580 pregnancies were obtained from 3315 cycles. Pregnancy outcome was unknown in 47 cases. The 533 pregnancies resulted in 410 deliveries and 463 live births. The result of female HIV testing after assisted reproduction was known in 967 out of 1036 woman (7.1% lost to follow-up). All tests recorded were negative. The calculated probability of contamination was equal to zero (95% confidence interval, 0-0.09%). CONCLUSION: This first multicentre retrospective study of assisted reproduction following sperm washing demonstrates the method to be effective and to significantly reduce HIV-1 transmission risk to the uninfected female partner. These results support the view that assisted reproduction with sperm washing could not be denied to serodiscordant couples in developed countries and, where possible, could perhaps be integrated into a global public health initiative against HIV in developing countries.     

What is the benefit of preoperative sperm preservation for patients who undergo restorative proctocolectomy for benign diseases?

PURPOSE: In patients with benign colorectal diseases undergoing a restorative proctocolectomy with an ileal pouch-anal anastomosis, semen cryopreservation seems rational to enable the possibility of procreation in case surgery leads to sexual disorders or impotence. The aim of this study was to determine the preoperative and postoperative semen quality in patients undergoing ileal pouch-anal anastomosis. In addition, the study sought to determine the incidence of surgery-induced sexual dysfunction to evaluate the economic efficiency of semen cryopreservation as compared with alternatives such as microsurgical epididymal sperm aspiration. METHODS: Preoperative and postoperative semen analyses were offered to 97 patients with ileal pouch-anal anastomosis with benign colorectal diseases since 1989. The direct costs of the semen cryopreservation program were determined and compared with those of alternatives. RESULTS: In 34 of 40 consecutive patients with ileal pouch-anal anastomosis who made use of preoperative semen preservation, normal sperm concentrations, motility, and morphology were found. Mean semen characteristics of all 23 patients who returned for postoperative analysis were not different from preoperative values, but they were for total sperm number. Two patients developed temporary retrograde ejaculation postoperatively. None of the preserved semen samples was used, thus semen cryopreservation benefited none of these patients. The total costs of semen cryopreservation are between 2.2 and 5 times higher than the costs for one microsurgical epididymal sperm aspiration procedure. CONCLUSIONS: Preoperative semen cryopreservation in patients undergoing ileal pouch-anal anastomosis because of benign colorectal diseases is quite feasible. However, most likely because of improved surgical techniques and the increasing number of effective alternatives, preoperative semen cryopreservation in patients with ileal pouch-anal anastomosis is no longer cost effective.Presented at the meeting of The Society for Surgery of the Alimentary Tract, Orlando, Florida, May 16 to 19, 1999.