In-vitro culture of spermatozoa induces motility and increases implantation and pregnancy rates after testicular sperm extraction and intracytoplasmic sperm injection

Sperm Selection Procedures for Optimizing the Outcome of ICSI in Patients with NOA

Retrieving spermatozoa from the testicles has been a great hope for patients with non-obstructive azoospermia (NOA), but relevant methods have not yet been developed to the level necessary to provide resolutions for all cases of NOA. Although performing testicular sperm extraction under microscopic magnification has increased sperm retrieval rates, in vitro selection and processing of quality sperm plays an essential role in the success of in vitro fertilization. Moreover, sperm cryopreservation is widely used in assisted reproductive technologies, whether for therapeutic purposes or for future fertility preservation. In recent years, there have been new developments using advanced technologies to freeze and preserve even very small numbers of sperm for which conventional techniques are inadequate. The present review provides an up-to-date summary of current strategies for maximizing sperm recovery from surgically obtained testicular samples and, as an extension, optimization of in vitro sperm processing techniques in the management of NOA.

Effect of in vitro testicular spermatozoa culture on pregnancy outcomes: an experience at a single university hospital

Background

There are no guidelines for the optimal incubation time or temperature to improve pregnancy outcomes in testicular sperm extraction-intracytoplasmic sperm injection (TESE-ICSI) cycles. We aimed to evaluate whether a 24-hour in vitro culture of testicular spermatozoa affects pregnancy outcomes in TESE-ICSI cycles.

Methods

This was a retrospective study of 83 TESE-ICSI cycles using testicular spermatozoa in 46 couples with male partners suffering from nonobstructive or obstructive azoospermia. Sperm retrieval was performed either on the oocyte retrieval (OR) day (65 cycles in 33 couples; group A) or on the day before OR (18 cycles in 13 couples; group B) followed by in vitro culture for 24 hours. The clinical characteristics and pregnancy outcomes, including the number of retrieved oocytes, fertilization rates, embryo transfer rates, implantation and clinical pregnancy rates, were compared between the two groups.

Results

There were no differences in terms of clinical characteristics except for the levels of luteinizing hormone (LH) in males. Group B had higher LH levels than group A (4.56±1.24 IU/L vs. 3.67±1.07 IU/L, p=0.017). Group B showed higher fertilization rate (72.4%±32.1% vs. 59.2%±21.7%, p=0.045), implantation rate (35.0%±34.1% vs. 14.0%±21.5%, p=0.010), pregnancy rate per cycle (80% vs. 39%, p=0.033), and clinical pregnancy rate per cycle (80% vs. 37.5%, p=0.024) than those of group A.

Conclusion

Testicular sperm retrieval performed on the day before OR followed by in vitro culture can potentially improve pregnancy outcomes.

Relationship between the positions of cytoplasmic granulation and the oocytes developmental potential in human

To evaluate the relationship between the positions of cytoplasmic granulation and the oocytes developmental potential in human, we detected the developmental potentials of oocytes with centrally located cytoplasmic granulation (CLCG). The patients’ age, body mass index (BMI), Infertility duration, follicle stimulation hormone (FSH) levels, average stimulate ovulation days, gonadotropin (GN) total dose, fertilization rate, cleavage rate, high quality embryo rate, embryo utilization rate and pregnancy rate were analyzed. The results showed that there were no significant difference on patients’ age, BMI, infertility duration, FSH levels, average stimulate ovulation days, GN total dose, pregnancy rate and birth rate between CLCG group and control group in patients with BMI < 24 (P > 0.05). However, there was no significant difference in fertilization rate, cleavage rate, and high quality embryo rate in patients with BMI < 24 (P > 0.05). The pregnancy rate was low in both groups, but 35 and 15 healthy fetuses were born in each group. We also found that the central granulated area size did not affect fertilization rate, cleavage rate, embryo utilization rate, and high quality embryo rate (P > 0.05). These results suggested CLCG might be a normal morphology of oocyte. The oocytes from patients with or without CLCG had no significant difference in their developmental potentials. The patients who transferred CLCG embryos had successful delivery. The developmental potentials of oocytes with different CLCG grades had no obvious differences.

Improvement of motility after culture of testicular spermatozoa: the effects of incubation timing and temperature

Background

Sperm motility is the reliable parameter that roles in success of intracytoplasmic sperm injection (ICSI), especially in azoospermia. Selection of appropriate culture duration, temperature and media for enhancing the sperm motility is an important issue in assisted reproduction program. The aim was to evaluate the sperm motion characteristics after culturing of testicular sperm extraction (TESE) samples at different temperatures and time intervals.

Methods

In this prospective study, 27 TESE samples were collected from young azoospermic patients. The samples were cultured in Ham’s F10+20% HAS, at different temperatures (incubation at 37 vs. 25 °C) and sperm total motility was assessed at different time intervals of 0, 24, 48 and 72 h post testicular biopsy.

Results

In vitro culture at 25 °C changed sperm motility from 13% immediately after biopsy to 76% at 24 h, 43% at 48 h and 15% at 72 h. At 37 °C, the sperm motion feature was changed to 67% at 24 h, 38.40% at 48 h and 12.03% at 72 h. Sperm motility change at 24 h was incremental in both conditions of culturing, but significant at 25 °C (P≤0.05).

Conclusions

The ideal in vitro culture for testicular spermatozoa was at 25 °C after 1 day of culture, which optimized the sperm motility in azoospermic TESE samples.

Processing and selection of surgically-retrieved sperm for ICSI: a review

Although the technique of intracytoplasmic sperm injection (ICSI) has been a revolution in the alleviation of male infertility, the use of testicular sperm for ICSI was a formerly unseen breakthrough in the treatment of the azoospermic man with primary testicular failure. At the clinical level, different procedures of testicular sperm retrieval (conventional TESE, micro-TESE, FNA/TESA, MESA, PESA) are being performed, the choice is mainly based on the cause of azoospermia (obstructive versus non-obstructive) and the surgeon's skills. At the level of the IVF laboratory, mechanical procedures to harvest the sperm from the tissue may be combined with enzymatic treatment in order to increase the sperm recovery rates. A number of techniques have been developed for viable sperm selection in males with only immotile testicular sperm available. However, large, well-designed studies on the benefit and safety of one over the other technique are lacking. Despite all the available methods and combinations of laboratory procedures which have a common goal to maximize sperm recovery from testicular samples, a large proportion of NOA patients fail to father a genetically own child. Advanced technology application may improve recovery rates by detection of the testicular foci with active spermatogenesis and/or identification of the rare individual sperm in the testicular suspensions. On the other hand, in vitro spermatogenesis or sperm production from embryonic stem cells or induced pluripotent stem cells might be future options. The present review summarizes the available strategies which aim to maximize sperm recovery from surgically retrieved samples.

Models of in vitro spermatogenesis

Understanding the mechanisms that lead to the differentiation of male germ cells from their spermatogonial stem cells through meiosis to give rise to mature haploid spermatozoa has been a major quest for many decades. Unlike most other cell types this differentiation process is more or less completely dependent upon the cells being located within the strongly structured niche provided by mature Sertoli cells within an intact seminiferous epithelium. While much new information is currently being obtained through the application and description of relevant gene mutations, there is still a considerable need for in vitro models with which to explore the mechanisms involved. Not only are systems of in vitro spermatogenesis important for understanding the basic science, they have marked pragmatic value in offering ex vivo systems for the artificial maturation of immature germ cells from male infertility patients, as well as providing opportunities for the transgenic manipulation of male germ cells. In this review, we have summarized literature relating to simplistic culturing of germ cells, co-cultures of germ cells with other cell types, especially with Sertoli cells, cultures of seminiferous tubule fragments, and briefly mention the opportunities of xenografting larger testicular pieces. The majority of methods are successful in allowing the differentiation of small steps in the progress of spermatogonia to spermatozoa; few tolerate the chromosomal reduction division through meiosis, and even fewer seem able to complete the complex morphogenesis which results in freely swimming spermatozoa. However, recent progress with complex culture environments, such as 3-d matrices, suggest that possibly success is now not too far away.

Increased fertilization rates after in vitro culture of frozen-thawed testicular immotile sperm in nonobstructive azoospermic patients

Objective. To optimise the use of freeze/thaw testicular immotile spermatozoa from nonobstructive azoospermia patients and to analyse the outcome of intracytoplasmic sperm injection (ICSI) of such spermatozoa. Methods. Testicular specimens were retrieved and cryopreserved from forty patients with nonobstructive azoospermia and underwent one cycle with thawed spermatozoa (Group I) that led to pregnancy in sixteen cases. Twenty-four patients of group I underwent treatment with the same batch of thawed spermatozoa (Group II). For the first ICSI attempt, injection was performed when motile spermatozoa were found. In group II, injection was performed when maximum motility was reached. We compared mean of fertilization rate, embryo quality, clinical pregnancy rate and embryo implantation rate. Results. The mean percentage of motility was significantly higher in the group II than in the group I (18, 6 versus 8, 2). Group I showed a significant decrease in fertilization rates when compared with cryopreserved testicular spermatozoa in group II (54% versus 72%, P < 0.05). No difference was noted between the cleavage rate, embryo quality, clinical pregnancy rates and implantation rates among group II and I. Conclusion. Fecundation rate can be significantly improved after in-vitro culture and sperm selection of frozen-thawed immotile testicular spermatozoa in patients with nonobstructive azoospermia.

Cellular biophysics during freezing of rat and mouse sperm predicts post-thaw motility

Though cryopreservation of mouse sperm yields good survival and motility after thawing, cryopreservation of rat sperm remains a challenge. This study was designed to evaluate the biophysics (membrane permeability) of rat in comparison to mouse to better understand the cooling rate response that contributes to cryopreservation success or failure in these two sperm types. In order to extract subzero membrane hydraulic permeability in the presence of ice, a differential scanning calorimeter (DSC) method was used. By analyzing rat and mouse sperm frozen at 5 degrees C/min and 20 degrees C/min, heat release signatures characteristic of each sperm type were obtained and correlated to cellular dehydration. The dehydration response was then fit to a model of cellular water transport (dehydration) by adjusting cell-specific biophysical (membrane hydraulic permeability) parameters L(pg) and E(Lp). A "combined fit" (to 5 degrees C/min and 20 degrees C/min data) for rat sperm in Biggers-Whitten-Whittingham media yielded L(pg) = 0.007 microm min(-1) atm(-1) and E(Lp) = 17.8 kcal/mol, and in egg yolk cryopreservation media yielded L(pg) = 0.005 microm min(-1) atm(-1) and E(Lp) = 14.3 kcal/mol. These parameters, especially the activation energy, were found to be lower than previously published parameters for mouse sperm. In addition, the biophysical responses in mouse and rat sperm were shown to depend on the constituents of the cryopreservation media, in particular egg yolk and glycerol. Using these parameters, optimal cooling rates for cryopreservation were predicted for each sperm based on a criteria of 5%-15% normalized cell water at -30 degrees C during freezing in cryopreservation media. These predicted rates range from 53 degrees C/min to 70 degrees C/min and from 28 degrees C/min to 36 degrees C/min in rat and mouse, respectively. These predictions were validated by comparison to experimentally determined cryopreservation outcomes, in this case based on motility. Maximum motility was obtained with freezing rates between 50 degrees C/min and 80 degrees C/min for rat and at 20 degrees C/min with a sharp drop at 50 degrees C/min for mouse. In summary, DSC experiments on mouse and rat sperm yielded a difference in membrane permeability parameters in the two sperm types that, when implemented in a biophysical model of water transport, reasonably predict different optimal cooling rate outcomes for each sperm after cryopreservation.

[Testicular sperm extraction and intracytoplasmic sperm injection : Are there useful predictors of pregnancy and take home baby rate?]

Among married couples in Germany, 3-9% suffer from infertility. Due to the tremendous changes in reproductive medicine, several successful approaches including ICSI after operative sperm retrieval are available.The age of the woman has a positive predictive value for the ICSI outcome, but for the male partner no predictive value for any parameter before TESE and ICSI has been demonstrated. Therefore we investigated whether there is a parameter before TESE that will elucidate the question of success of assisted reproduction after successful sperm retrieval.The outcome of 108 married couples that were treated consecutively for infertility with one or more TESE were investigated to determine whether the man's age, FSH concentration or testicular volume has a significant influence on the success of this therapy. None of the parameters had a positive predictive value about the outcome that could enhance the counselling of these couples before operative sperm retrieval.

Viable pregnancies can occur after 24-hour incubation of ejaculated sperm before intracytoplasmic sperm injection

This is the first report of viable pregnancies established with ICSI after 24-hour incubation of washed ejaculated sperm from men with poor sperm parameters. Because both pregnancy rates and viable pregnancy rates were significantly increased compared with 2- to 4-hour-incubated historical controls, 24-hour incubation before ICSI may be beneficial in selecting the most favorable ejaculated sperm.

In vitro culture of testicular germ cells: regulatory factors and limitations

Spermatogenesis is regulated mainly by endocrine factors and also by testicular paracrine/autocrine growth factors. These factors are produced by Sertoli cells, germ cells, peritubular cells and interstitial cells, mainly Leydig cells and macrophages. The interactions and the ratio between Sertoli and germ cells in the seminiferous tubules ensure successful spermatogenesis. In order to culture spermatogonial stem cells (SSCs) in vitro, researchers tried to overcome some of the obstacles -- such as the low number of stem cells in the testis, absence of specific markers to identify SSCs -- in addition to difficulties in keeping the SSCs alive in culture. Recently, some growth factors important for the proliferation and differentiation of SSCs were identified, such as glial cell line derived neurotrophic factor (GDNF), stem cell factor (SCF) and leukemia inhibitory factor (LIF); also, markers for SSCs at different stages were reported. Therefore, some groups succeeded in culturing SSCs (under limitations), or more differentiated cells and even were able to produce in vitro germ cells from embryonic stem cells. Thus, success in culturing SSCs is dependent on understanding the molecular mechanisms behind self-renewal and differentiation. Culture of SSCs should be a good tool for discovering new therapeutic avenue for some infertile men or for patients undergoing chemotherapy/radiotherapy (pre-puberty or post-puberty).

Extended culture of human spermatozoa in the laboratory may have practical value in the assisted reproductive procedures

Spermatozoa were cultured in vitro to monitor time-dependent changes in motility, viability, morphology, and membrane integrity. The degree of preservation of these clinically relevant sperm parameters over time was satisfactory. Extended culture probably can be used as a transient storage for sperm to compensate for a male's inability to produce sperm to synchronize oocyte retrieval in assisted reproduction.

Effects of high doses of recombinant human follicle-stimulating hormone in the treatment of male factor infertility: results of a pilot study

We performed a randomized double-blind placebo-controlled study on seminal parameters and endocrine profile of 30 normogonadotropic patients with male factor infertility to assess the efficacy of treatment with recombinant human FSH (rhFSH) at high doses (300 IU on alternate days) for a period of >or=4 months. The treatment induced a marked increase in sperm count, a slight increase in sperm motility, no change in sperm morphology, and an evident increase only in FSH serum levels, showing that a prolonged treatment with rhFSH at high doses led to an evident improvement of sperm count in normogonadotropic infertile patients with idiopathic oligoasthenozoospermia.

The treatment of obstructive azoospermia by intracytoplasmic sperm injection

Intracytoplasmic sperm injection (ICSI) allows the treatment of virtually every type of male infertility. Unlike in vitro fertilization (IVF), its success does not depend on sperm concentration, motility or morphology and most of the physical barriers to fertilisation are by-passes. Since ICSI does not require strongly motile sperm, its use has now been expanded to incorporate immature sperm from the testes and epididymides. Successful fertilisation, pregnancies and healthy babies have all been reported. However, concerns about the safety of ICSI remain due to its short clinical history and the lack of testing on animal models.

Male fertility potential for assisted reproduction by ICSI cannot be measured by conventional parameters. Sperm DNA integrity is increasingly recognised as a more useful indicator. Studies have shown that sperm with higher levels of DNA damage have lower fertilisation rates after IVF and ICSI. Sperm with DNA damage above a certain threshold are associated with a longer time to conceive in otherwise apparently fertile couples and a higher miscarriage rate. DNA damage has been shown to be associated with impaired embryo cleavage. Our group has shown that sperm DNA from testicular sperm is less fragmented than that from epididymal sperm and suggest its preferred use in ICSI.

In addition to nuclear (n) DNA we also assessed the quality of mitochondrial (mt) DNA from testicular sperm from men with obstructive azoospermia undergoing ICSI. We observed that couples achieving a pregnancy had both less mtDNA deletions and less nDNA fragmentation. We found inverse relationships between pregnancy and sperm mtDNA deletion numbers, size and nDNA fragmentation. No relationships were observed with fertilisation rates. With this knowledge, we designed an algorithm for the prediction of pregnancy based on the quality of sperm nDNA and mtDNA.

Each year 40,000 men have a vasectomy in the UK but every year 2500 request a reversal to begin a second family. For such men, vasectomy reversal has recently been replaced in part by testicular biopsy via fine-needle testicular sperm aspiration (TESA) or percutaneous epididymal sperm aspiration (PESA) performed at an outpatient clinic and subsequently used in ICSI. Since these were previously fertile men it has been assumed that they had ‘fertile’ sperm. However the assited conception success rates of these mens partners has not been assessed until recently. We have shown a significant reduction in the clinical pregnancy rates in the partners of men who had had a vasectomy ≥10yrs previously. There is also evidence to suggest that spermatogenesis is significantly impaired in vasectomised men. Marked decreases in spermatocytes, spermatids and spermatozoa have been observed. We have found this to be associated with concomitant increases in apoptotic markers, such as Fas, FasL and Bax. The quality of the remaining sperm is also compromised. Sperm DNA from vasectomized men shows substantial damage which increases with time after surgery. This new use of ICSI will be discussed.

Efforts to create an artificial testis: culture systems of male germ cells under biochemical conditions resembling the seminiferous tubular biochemical environment

Induction of meiotic and post-meiotic alterations of male germ cells in vitro has been the target of several research efforts since 1960. However, to date, the establishment of an ideal culture system in which spermatogonial stem cells can be maintained and directed to proliferate and undergo meiosis and complete spermiogenesis does not exist. This is attributed to the difficulties concerning the isolation and purification of defined subpopulations of germ cells and the establishment of male germ cell lines. In addition, there is no adequate knowledge regarding the optimal biochemical conditions that promote the survival and differentiation of germ cells in long-term cultures. This review focuses on the methodologies that have been proved sufficient to achieve differentiation of cultured male germ cells. Furthermore, the factors regulating spermatogenesis and the technical prerequisites to achieve differentiation of cultured male germ cells are described. Finally, the role of in vitro cultures of immature diploid germ cells in the therapeutic management of men negative for haploid cells in their testes and the subsequent potential genetic and epigenetic risks are discussed.

Effects of short and long incubations on DNA fragmentation of testicular sperm

DNA fragmentation in testicular sperm from men with obstructive azoospermia is increased by 4-hour and 24-hour incubations and after cryopreservation with the effect is intensified by post-thaw incubation. Testicular sperm for use in intracytoplasmic sperm injection (ICSI) should be injected without delay.

Possible predictive factors for ICSI? Molecular biology techniques in combination with therapeutic testicular biopsies

Applying intracytoplasmic sperm injection (ICSI), the selection of an unsuccessful spermatozoon results in great emotional consequences for the couple. Therefore, there is a need for a prognostic parameter to estimate their chances for successful fertility treatment. This review summarizes both the main reasons for spermatogenic impairment, and possible predictive factors for successful sperm retrieval applying testicular sperm extraction and outcome of ICSI. While basic sperm parameters, aetiology and type of spermatozoa, and serum follicle-stimulating hormone and inhibin levels have been shown to be unrelated to the outcome of ICSI, Y-chromosome microdeletions are known to have a negative influence on the fertilizing capacity of spermatozoa. Recently, a significant correlation has been reported between the protamine-1 to protamine-2 mRNA ratio in haploid spermatids of testicular biopsies and the ability of spermatozoa for successful fertilization of an oocyte. In future, both the outstanding role of the haploid spermatids and the involvement of molecular biological techniques will improve the role of therapeutic testicular biopsies.

Comparison of the ICSI outcome of ejaculated sperm with normal, abnormal parameters and testicular sperm

OBJECTIVE(S)

To compare fertilization rates, quality of embryos, pregnancy rates (PRs) and outcome of pregnancies in intracytoplasmic sperm injection (ICSI) using sperm from ejaculates of normal and abnormal semen and testicular sperm of non-obstructive azoospermia.

STUDY DESIGN

Four hundred fifty-four patients who underwent 454 ICSI cycles were evaluated retrospectively. Patients were divided into three groups according to the quality and source of sperm. Patients in group 1 underwent 133 cycles of ICSI using ejaculated normal semen, group 2 underwent 235 cycles using ejaculated abnormal semen, and group 3 underwent 86 cycles using testicular sperm.

RESULTS

The parameters were compared among the groups with respect to cycles induced by long (n = 160) and short (n = 294) protocol. In group 3, the fertilization and PRs were significantly lower than in all other groups (51.3 and 10.6% in the long protocol cycles, 53.3 and 5.1% in the short protocol cycles, respectively). There was no significant difference in the outcome of pregnancies in respect to abortion rates between different groups.

CONCLUSION(S)

The fertilizing ability of sperm in ICSI is highest with ejaculated sperm and lowest with sperm extracted by testicular biopsy. Also, the clinical PRs are significantly lower in ICSI with sperm from testicular biopsy. However, the outcomes of pregnancies are not affected by using surgically retrieved sperm from ejaculated semen.

Predictive value of testicular histology in secretory azoospermic subgroups and clinical outcome after microinjection of fresh and frozen-thawed sperm and spermatids

BACKGROUND

A retrospective study was carried out on 159 treatment cycles in 148 secretory azoospermic patients to determine whether histopathological secretory azoospermic subgroups were predictive for gamete retrieval, and to evaluate outcome of microinjection using fresh or frozen-thawed testicular sperm and spermatids.

METHODS

Sperm and spermatids were recovered by open testicular biopsy and microinjected into oocytes. Fertilization and pregnancy rates were assessed.

RESULTS

In hypoplasia, 97.7% of the 44 patients had late spermatids/sperm recovered. In maturation-arrest (MA; 47 patients), 31.9% had complete MA, and 68.1% incomplete MA due to a focus of early (36.2%) or late (31.9%) spermiogenesis. Gamete retrieval was achieved in 53.3, 41.2 and 93.3% of the cases respectively. In Sertoli cell-only syndrome (SCOS; 57 patients), 61.4% were complete SCOS, whereas incomplete SCOS cases showed one focus of MA (5.3%), or of early (29.8%) and late (3.5%) spermiogenesis. Only 29.8% of the patients had a successful gamete retrieval, 2.9% in complete and 77.3% in incomplete SCOS cases. In total, there were 87 ICSI, 39 elongated spermatid injection (ELSI) and 33 round spermatid injection (ROSI) treatment cycles, with mean values of fertilization rate of 71.4, 53.6 and 17%, and clinical pregnancy rates of 31.7, 26.3 and 0% respectively.

CONCLUSIONS

Histopathological subgroups were positively correlated with successful gamete retrieval. No major outcome differences were observed between testicular sperm and elongated spermatids, either fresh or frozen-thawed. However, injection of intact round-spermatids showed very low rates of fertilization and no pregnancies.

Development of a new and efficient laboratory method for processing testicular sperm

PURPOSE

Testicular biopsy specimens contain large amounts of debris that makes sperm pick-up for ICSI more difficult than with epididymal aspirates. We sought to develop improved processing techniques for testicular sperm extraction (TESE).

METHODS

Retrievals were with azoospermic male partner scheduled to undergo percutaneous epididymal sperm aspiration (PESA) and TESE. The study group consisted of 9 retrievals with a new TESE technique (TESE-N). The control group was 21 retrievals with PESA and 3 retrievals with a previous TESE technique (TESE-P).

RESULTS

TESE-N eliminated almost all debris, which made ICSI sperm pick-up more rapid. TESE-N, PESA, and TESE-P fertilization (77, 75, and 72%) and ongoing/delivered pregnancy rates per retrieval (67, 76, and 67%) were similar.

CONCLUSIONS

Our new technique provides for easy removal of debris from TESE specimens and fertilization and pregnancy rates equal to epididymal sperm's. Eliminating debris from TESE specimens allows for rapid sperm pick-up for ICSI, making the procedure more efficient for embryology staff.

Transfer at the blastocyst stage of embryos derived from testicular round spermatid injection

BACKGROUND

Intracytoplasmic injection of testicular round spermatids has been suggested as a salvage treatment in couples when testicular sperm extraction does not yield any mature sperm. However, the success of the procedure is debatable, and controversy surrounds issues such as the presence and (if present) identification of spermatids in testicular tissue. Progression rate to the blastocyst stage of spermatid-derived embryos appears to be low.

METHODS

In this study, we investigated the feasibility and outcome of blastocyst stage embryo transfer after round spermatid injection (ROSI). ROSI was undertaken in 58 couples who did not yield mature or elongated sperm to testicular sperm extraction.

RESULTS

The incidence of blastocyst formation from two pronuclear oocytes was 7.6%. A total of 16 blastocysts were transferred in 12 patients (20.7%). None of the patients conceived.

CONCLUSIONS

The results of this study indicate that the blastocyst stage is reached by only very few ROSI-derived embryos and these embryos do not implant.

Assisted conception in the azoospermic male

The advent of intracytoplasmic sperm injection (ICSI) has offered new solutions for the management of patients with azoospermia. Surgical sperm recovery combined with ICSI has allowed many men with azoospermia to father their own biological children. Azoospermia can be classified as obstructive and non-obstructive, with investigations, management and success rates varying markedly between the two forms. In certain cases of obstructive azoospermia surgical reconstruction remains a viable option, whereas cases with congenital obstruction need to be screened for mutations of the cystic fibrosis gene. In most cases of obstruction sperm can be retrieved from the epididymis using percutaneous epididymal sperm aspiration (PESA). If PESA is unsuccessful, testicular sperm extraction (TESE) is successful in all cases. With non-obstructive azoospermia, the genetic basis has been investigated intensely. Screening for karyotypic abnormalities as well as Y microdeletions is recommended. Irrespective of the histological diagnosis, focal spermatogenesis can be observed in 40-50% of cases using multiple testicular biopsies.

Intracytoplasmic sperm injection with testicular spermatozoa in men with azoospermia

PURPOSE

The aim of the study was to gain an insight into the optimal management of the infertile couple with the husband suffering from azoospermia.

METHODS

One hundred and forty-two intracytoplasmic sperm injection (ICSI) cycles performed with testicular extracted spermatozoa were retrospectively analysed. The following factors were investigated for their possible influence on fertilization, cleavage, damage, pregnancy, and ongoing pregnancy rates: the use of fresh, cryopreserved, and preincubated (24 h) spermatozoa and the etiology of the husbands' azoospermia (obstructive and nonobstructive). All microinjections were performed with apparently normal spermatozoa--a head with a tail of normal length. In 116 cycles at least two embryos were available for transfer.

RESULTS

The overall fertilization, clinical pregnancy, and ongoing pregnancy rates obtained for the 116 cycles were 65.0, 30.2, and 22.4% respectively. Similar outcomes were obtained for cycles using fresh testicular and cryopreserved testicular spermatozoa. Similarly, no significant differences were obtained between the cycles using spermatozoa from obstructive or nonobstructive azoospermic patients. An increase in motility after a 24-h preincubation was observed, and although this group was relatively small (n = 17), a significant improvement in fertilization (73.7%) and pregnancy (53.9%) rate was obtained when the testicular sample was preincubated for 24 h. This improvement prevailed in the obstructive azoospermic group, but was less pronounced in nonobstructive patients.

CONCLUSIONS

This study shows that the outcome of fresh and frozen-thawed testicular spermatozoa in ICSI is comparable, obstructive and nonobstructive etiologies perform the same, and that preincubation of testicular spermatozoa results in increased fertilization and pregnancy rates. All testicular biopsies are therefore performed the day before oocyte retrieval, superfluous spermatozoa cryopreserved, and the remaining testicular homogenate preincubated for the 24 h prior to oocyte retrieval. With this regime, most azoospermic patients are treated successfully, irrespective of the use of fresh or frozen-thawed spermatozoa from obstructive or nonobstructive cases.

Timing of testicular sperm retrieval procedures and in vitro fertilization-intracytoplasmic sperm injection outcome

OBJECTIVE

To compare the outcome of IVF-intracytoplasmic sperm injection (ICSI) using testicular spermatozoa obtained on the day of ovum pick-up (OPU) or on the day before OPU.

DESIGN

Retrospective study.

SETTING

An IVF clinic in a university hospital.

PATIENT(S)

Forty-seven IVF-ICSI cycles using testicular spermatozoa in 28 couples with the male partner suffering from nonobstructive azoospermia.

INTERVENTION(S)

Sperm retrieval was performed either on the OPU day (23 cycles in 19 patients; group A) or on the day before OPU (24 cycles in 15 patients; group B). Testicular sperm aspiration (TESA) was performed and followed by testicular sperm extraction (TESE) if no spermatozoa could be found.

MAIN OUTCOME MEASURE(S)

The presence of motile spermatozoa at the time of ICSI and fertilization and clinical pregnancy rates.

RESULT(S)

A similar proportion of motile spermatozoa (60.9% vs. 62.5%), fertilization rate (61.7% vs. 58.9%), and clinical pregnancy rate per transfer (34.8% and 29.2%) were obtained for groups A and B, respectively.

CONCLUSION(S)

Testicular sperm retrieval can be performed on the day before OPU without compromising success. Considerable medical and practical advantages may be offered by further advancement of testicular sperm retrieval procedures to 48 hours before OPU. This approach should thus be further evaluated.

Blastocyst transfer following intracytoplasmic injection of ejaculated, epididymal or testicular spermatozoa

Recent studies indicate a strong paternal influence on embryo development and progression of the embryo to the blastocyst stage. The aim of this study was to compare, during extended culture, the in-vitro development of embryos resulting from intracytoplasmic sperm injection (ICSI) of ejaculated spermatozoa (group 1, n = 347), epididymal (group 2, n = 22) or testicular (group 3, n = 18) spermatozoa from obstructive azoospermic and testicular spermatozoa from non-obstructive azoospermic (group 4, n = 31) subjects. Fertilization and blastocyst formation rates were significantly lower in group 4 (P < 0.05). The incidence of expanded and hatching blastocysts was significantly lower in group 4 (P < 0.05). Overall in 93.2% ejaculate ICSI cycles, blastocysts were transferred on day 5. This was significantly higher than the 62% day 5 transfers in the non-obstructive azoospermic group (P < 0.05). Implantation rate per embryo was significantly higher in the ejaculate ICSI group compared with the other groups (P < 0.05). Clinical pregnancy per transfer was similar between groups; however, significantly fewer multiple pregnancies were encountered in the non-obstructive azoospermic group (P < 0.01). In conclusion, the source of the spermatozoa, most likely to be indicative of the severity of spermatogenic disorder, affects the rate of blastocyst formation and blastocyst implantation. Spermatozoa from non-obstructive azoospermic subjects, when utilized for ICSI, result in embryos that progress to the blastocyst stage at a lower and slower rate and implant less efficiently.

Nonobstructive azoospermia

Nonobstructive azoospermia (NOA) remains a challenging condition in reproductive medicine to manage. The genetic basis of NOA related to partial deletions of the Y-chromosome has been intensely investigated. Such information is of prognostic value and allows more insightful genetic counseling of couples who opt for assisted reproductive technology. Testicular sperm extraction (TESE) combined with intracytoplasmic sperm injection has allowed many men with NOA to father their own biologic children. Although studies in the current literature support open testicular biopsy as the most reliable method to obtain testicular sperm, less invasive techniques such as testicular fine-needle aspiration and percutaneous needle biopsy are feasible alternatives in selected groups of patients. Measures to improve the efficacy of TESE, including the application of microsurgical techniques, are addressed. Other recent developments related to the management of NOA reviewed include processing of testicular tissue, cryopreservation of retrieved spermatozoa, in-vitro maturation of germ cells and microinjection of immature spermatogenic precursor cells.

Pure follicle-stimulating hormone as an adjuvant therapy for selected cases in male infertility during in-vitro fertilization is beneficial

OBJECTIVES

Since research has demonstrated the possibility of hormonal therapy for male infertility, we conducted a study to analyze the efficacy of pure follicle-stimulating hormone (pFSH) treatment in patients with idiopathic, severe oligoteratoastheno-spermia (OTA) syndrome, or failed fertilization before referral to an intracytoplasmic sperm injection (ICSI) in an in-vitro fertilization (IVF) program.

STUDY DESIGN

A retrospective, clinical study was carried out on 178 men with OTA syndrome. Group I comprised 76 patients selected for treatment with pFSH. Group II comprised 102 men who served as the controls. Pure FSH was administered intramuscularly to the patients in group I. Upon cessation of therapy, an IVF treatment cycle was carried out.

RESULTS

After treatment with FSH, sperm motility was the only parameter which significantly improved in Group I (34% vs. 23%, and 15% vs. 24% in the subgroups of Group 1, respectively; P<0.05). In-vitro fertilization pregnancy rates were similar in both groups. The highest spontaneous pregnancy rates were achieved in FSH-treated, severe OTA patients.

CONCLUSIONS

Patients with severe male factor infertility may benefit from pFSH in terms of sperm motility, fertilization by IVF and spontaneous pregnancy rates. Selection criteria for FSH treatment are proposed.

Triploid pregnancy after ICSI of frozen testicular spermatozoa into cryopreserved human oocytes: case report

Although freezing oocytes is ethically more acceptable than cryopreservation of embryos, variable oocyte survival, fertilization rate and possible risk of increased ploidy after cryopreservation have precluded the widespread clinical application of oocyte cryopreservation in assisted reproduction techniques. We report a triploid pregnancy from intracytoplasmic sperm injection of recombinant FSH-stimulated frozen/thawed testicular spermatozoa into cryopreserved oocytes in a hormone replacement cycle. To our knowledge, this is the first report of a pregnancy where both gametes have been frozen. It illustrates the need for further research when applying new techniques in assisted reproduction.

In-vitro maturation of immature human male germ cells

Both meiotic and postmeiotic maturation events have been observed to occur in human male germ cells during in-vitro culture. The temperature of 30 degrees C, medium supplementation with follicle-stimulating hormone and testosterone and the maintenance of the original cell-cell associations within explanted segments of the testicular seminiferous tubules are common features of the most efficient culture systems. The in-vitro maturation processes are markedly accelerated as compared to the in-vivo situation, probably due to the abrogation of a checkpoint controlling the full assembly of molecules needed for spermiogenesis. Moreover, both meiotic and postmeiotic maturation processes can be reactivated in vitro in some cases with a complete block of the same processes in vivo. Healthy babies were born after micromanipulation-assisted fertilization with in-vitro matured elongated spermatids from men with complete in-vivo maturation arrest at the round spermatid stage and at the primary spermatocyte stage.

Outcome of testicular sperm retrieval procedures in non-obstructive azoospermia: percutaneous aspiration versus open biopsy

The aim of this study was to evaluate whether the extraction of testicular spermatozoa with percutaneous versus open biopsy has an effect on the treatment outcome with intracytoplasmic sperm injection (ICSI) in men with non-obstructive azoospermia. Regardless of testicular size, follicle stimulating hormone concentration, and previous biopsy result, percutaneous testicular sperm aspiration (PTSA) using a 21-gauge butterfly needle was attempted first and if this failed testicular sperm extraction (TESE) was performed. In 63 men spermatozoa were found with PTSA whereas in 228 men TESE had to be undertaken. More men in the PTSA group had previously been diagnosed with hypospermatogenesis (82 versus 50%). Compared with the PTSA group, more men in the TESE group had germ cell aplasia (27 versus 10%) or maturation arrest (22 versus 8%). There was no difference between the groups regarding mean age of men and their partners, duration of stimulation, oestradiol concentration on the day of human chorionic gonadotrophin, number of oocytes retrieved, fertilization rate, and embryo quality between the two groups. The number of embryos transferred (4.38 versus 3.90) was significantly higher in the PTSA group (P < 0.05), reflecting the increased number of embryos available for transfer. Implantation rate per embryo was 20.7% in the PTSA and 13.3% in the TESE group (P < 0.05). Clinical pregnancy rates were 46 and 29% in the PTSA and TESE groups respectively (P < 0.05). Clinical abortion rates were similar (21.2 versus 24%). It is concluded that in men with non-obstructive azoospermia, easier sperm retrieval, which is most likely indicative of a more favourable histopathology, is associated with higher implantation rates per embryo.