Paternal effect on genomic activation, clinical pregnancy and live birth rate after ICSI with cryopreserved epididymal versus testicular spermatozoa

Reproductive and obstetric outcomes in TESE-ICSI cycles: A comparison between obstructive and non-obstructive azoospermia

PURPOSE

Comparison of intracytoplasmic sperm injection cycles with testicular sperm extraction in obstructive azoospermia and non-obstructive azoospermia are limited, and few studies have addressed obstetric and neonatal outcomes.

DESIGN

This study analyzed couples who underwent testicular sperm extraction-intracytoplasmic sperm injection cycles for obstructive azoospermia and non-obstructive azoospermia to determine whether impaired spermatogenesis in non-obstructive azoospermia patients would lead to worse reproductive outcomes and higher rates of pregnancy complications and fetal anomalies. This study is a retrospective, single-center analysis of all testicular sperm cycles performed between January 1, 2001 and December 31, 2020.

RESULTS

A total of 392 couples were considered in the study, leading to 1066 induction cycles, 620 (58.2%) from patients with obstructive azoospermia and 446 (41.8%) from non-obstructive azoospermia. The cumulative delivery rate did not significantly differ between the two groups (34% vs. 31%; p = 0.326). The miscarriage rate was similar between obstructive azoospermia and non-obstructive azoospermia patients. Fertilization rate instead showed a statistically significant difference (obstructive azoospermia: 66.1 ± 25.7 vs. non-obstructive azoospermia: 56.1 ± 27.0; p < 0.001). The overall maternal complication rate in the non-obstructive azoospermia group was higher (10.7% vs. 18.4%; p = 0.035), but there was no statistical significance for each pathology. There was no statistical difference in gestational age between the two groups for both single and twin pregnancies. Seven cases of congenital defects occurred in the obstructive azoospermia group, while two cases occurred in the non-obstructive azoospermia group.

CONCLUSIONS

Despite impaired spermatogenesis in non-obstructive azoospermia patients, there were no substantial differences in reproductive outcomes compared to patients with obstructive azoospermia, even in terms of obstetric safety and neonatal well-being.

Management of male factor infertility: position statement from the Italian Society of Andrology and Sexual Medicine (SIAMS) : Endorsing Organization: Italian Society of Embryology, Reproduction, and Research (SIERR)

PURPOSE

Infertility affects 15-20% of couples and male factors are present in about half of the cases. For many aspects related to the diagnostic and therapeutic approach of male factor infertility, there is no general consensus, and the clinical approach is not uniform.

METHODS

In the present document by the Italian Society of Andrology and Sexual Medicine (SIAMS), endorsed by the Italian Society of Embryology, Reproduction, and Research (SIERR), we propose evidence-based recommendations for the diagnosis, treatment, and management of male factor infertility to improve patient and couple care.

RESULTS

Components of the initial evaluation should include at minimum medical history, physical examination, and semen analysis. Semen microbiological examination, endocrine assessment, and imaging are suggested in most men and recommended when specific risk factors for infertility exist or first-step analyses showed abnormalities. Full examination including genetic tests, testicular cytology/histology, or additional tests on sperm is clinically oriented and based on the results of previous investigations. For treatment purposes, the identification of the specific cause and the pathogenetic mechanism is advisable. At least, distinguishing pre-testicular, testicular, and post-testicular forms is essential. Treatment should be couple-oriented, including lifestyle modifications, etiologic therapies, empirical treatments, and ART on the basis of best evidence and with a gradual approach.

CONCLUSION

These Guidelines are based on two principal aspects: they are couple-oriented and place high value in assessing, preventing, and treating risk factors for infertility. These Guidelines also highlighted that male infertility and in particular testicular function might be a mirror of general health of a man.

Male genome influences embryonic development as early as pronuclear stage

BACKGROUND

Impaired paternal genome expression may cause poor embryonic development after in vitro fertilization (IVF).

OBJECTIVE

To evaluate the expression of male infertility on embryo morphokinetics using a time-lapse incubator and its impact on IVF cycles.

MATERIALS AND METHODS

This retrospective cohort study followed patients from January 2017 to August 2019. Patients were divided according to the cause of infertility to male factor (study group) and unexplained infertility (control group) and further subdivided according to the severity of male infertility.

RESULTS

A cohort of 462 patients who underwent IVF cycles, with a total of 3,252 embryos was evaluated. Intracytoplasmic sperm injection (ICSI) was conducted more often in the study group compared to the control group (94% vs. 47%, p < 0.0001) and more embryos were discarded (47% vs. 43%, p = 0.016). Treatment outcomes were comparable in both groups regardless of the severity of male infertility. T3-T5 had a significant impact on embryo quality and more transfer and freeze compared to discard. Maternal age, number of aspirated oocytes, BMI, protocol used, and faster time to T3, T6 were significant in increasing chances of achieving pregnancy.

CONCLUSION

The paternal genome may have an earlier impact on embryo development than previously surmised and may also account for faster morphokinetics. Faster embryo cleavage in male infertility IVF-ICSI cycles may contribute to outcomes comparable to other causes of infertility, in terms of embryo quality and clinical pregnancy rate, despite lower sperm quality, even in cases of severe Oligo-terato-Astheno spermia (OTA).

TESE-ICSI outcomes per couple in vasectomized males are negatively affected by time since the intervention, but not other comorbidities

RESEARCH QUESTION

Does time since vasectomy (as obstructive interval) and the presence of different male comorbidities adversely affect the likelihood of achieving a newborn for vasectomized males undergoing testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI)?

DESIGN

This retrospective study included 364 couples with vasectomized males undergoing TESE-ICSI cycles with autologous oocytes at IVI Valencia. The main outcome was live birth rate (LBR). Subjects were divided according to the male risk factor evaluated into quartiles (obstructive interval, body mass index [BMI]) or groups (hypertension, diabetes mellitus, dyslipidaemia). The reproductive outcomes were calculated per embryo transfer, per ovarian stimulation completed, and per couple.

RESULTS

The average obstructive interval was 11.3 years. The LBR was 34.4% (95% CI 30.1-38.6) per embryo transfer, 27.8% (95% CI 24.1-31.5) per ovarian stimulation and 46.2% (95% CI 41.8-51.3) per couple. When considering obstructive interval, a significantly lower LBR per couple (P = 0.04) was found in the group with the longest obstruction time: Q1 42.1% (95% CI 33.5-50.7), Q2 49.1% (95% CI 36.1-62.1), Q3 56.3% (95% CI 46.7-65.9) and Q4 37.2% (95% CI 26.5-47.9) but the cumulative live birth rate (CLBR) was not affected (P = 0.63). LBR per ovarian stimulation of males with hypertension was significantly lower (P = 0.04) than healthy males: 13.5% (95% CI 2.5-24.5) and 28.6% (95% CI 24.7-32.5), respectively. The group of diabetic vasectomized males had a significantly higher CLBR (P = 0.02). The remaining risk factors assessed (smoking, dyslipidaemia and a high BMI) did not affect LBR compared with their healthy counterparts.

CONCLUSION

Time since vasectomy appears to negatively influence the LBR when assessed per couple. The CLBR was not affected by the obstructive interval or the presence of other male comorbidities apart from diabetes, which had a significant effect.

Impact of sperm characteristics on time-lapse embryo morphokinetic parameters and clinical outcome of conventional in vitro fertilization

BACKGROUND

Sperm abnormalities may negatively affect embryo development.

OBJECTIVES

To determine the influence of sperm abnormalities (morphology, motility, DNA fragmentation) on embryo morphokinetic variables and clinical outcome of conventional IVF.

MATERIALS AND METHODS

Participants were 86 couples undergoing in vitro fertilization (IVF). Sperm morphology was evaluated according to the strict criteria proposed by Kruger/Tygerberg. CASA system was applied for sperm motility assessment. Sperm DNA fragmentation was assessed by the chromatin structure assay (SCSA). Morphokinetic parameters were determined in 223 embryos obtained from conventional IVF only and cultured in a single-step medium using time-lapse imaging technology.

RESULTS

Time-lapse variables from the initial embryo development, such as time of pronuclei fading (tPNf) and time for two cells (t2), were those more strongly related with abnormalities of sperm motility, morphology, and DNA fragmentation. Sperm morphological abnormalities rather than sperm motility were more closely associated with embryo morphokinetics. Sperm head defects were mainly correlated with the last stages of embryonic development (t9 to tHB), sperm midpiece defects with intermediate cleaving embryos (t5-t9), and sperm tail defects with the initial stages of embryonic development (tPNa-t4). Excess residual cytoplasm was positively correlated with all embryo morphokinetic parameters except t2 and tM. Absence of acrosomes, pinheads, coiled tails, and multiple sperm morphological defects correlated negatively with time-lapse embryo morphokinetic variables.

DISCUSSION

A large number of sperm-related variables, including frequency of specific morphological defects, morphological indexes, DNA fragmentation and motility, and time-lapse embryo variables, such as time intervals based mainly of 15 time points were recorded.

CONCLUSION

There were strong associations between specific sperm defects of the head, midpiece, and tail with certain stages of embryonic development from observation of pronuclei to the hatched blastocyst. Coiled tail, cumulative head defects, and multiple abnormalities index (MAI) were associated both with embryo morphokinetics and the implantation success.

Azoospermia and embryo morphokinetics: testicular sperm-derived embryos exhibit delays in early cell cycle events and increased arrest prior to compaction

Purpose

Sperm play an essential role in embryonic genome activation and embryonic progression to blastocyst. In the present work, we focus on development of embryos created as a result of ICSI with testicular or epididymal sperm from azoospermic males and compare this to outcomes from normospermic males. The objective of this study was to determine if sperm origin influences clinical outcomes, the kinetics of embryo development, or the incidence of cleavage anomalies and multinucleation.

Methods

A total of 93 consecutive intracytoplasmic sperm injection cycles (ICSI) performed for 83 couples were included in this study. Observations were made on 594 fertilized oocytes cultured in the EmbryoScope using time-lapse microscopy (TLM). Epididymal sperm (n = 29) cycles or surgically retrieved sperm from the testis (TESE; n = 37 cycles) of men with either obstructive (OA) or non-obstructive azoospermia (NOA) were used to inject oocytes. A further 27 ICSI cycles were performed using ejaculated sperm from normospermic males, designated as our control sperm (CS) group. Kinetic data and cycle outcomes were retrospectively analyzed.

Results

The clinical pregnancy rate was not different between the three groups (TESE 51.4%, PESA 57.7%, and CS 59.3%). A non-significant decrease was observed in both implantation (30.9%) and live birth rate (43%) with TESE as compared to PESA (35.3%, 58%, respectively) and CS groups (45.1%, 56%, respectively). Failure to compact was significantly higher amongst TESE-NOA embryos (35.2%; P < 0.001) as compared to TESE-OA (4%), PESA (9%), and CS (3.8%) embryos. The two points at which TESE-derived embryos (both NOA and OA) behaved most differently from PESA and CS embryos was at cc2 (t3-t2; time to initiation of the second cell cycle) and tSB (time to start of blastulation). A significantly lower percentage of TESE embryos exhibited kinetics typically ascribed to high quality embryos with the greatest developmental potential. Finally, the incidence of direct uneven cleavage (DUC) was observed to be significantly higher after ICSI with sperm retrieved from azoospermic males.

Conclusions

TLM allowed a more in depth comparison of paternal influence on embryo morphokinetics and helped to identify specific differences in cell cycle kinetics. TESE-NOA embryos exhibited a higher incidence of compaction failure.

Dry Preservation of Spermatozoa: Considerations for Different Species

The current gold standard for sperm preservation is storage at cryogenic temperatures. Dry preservation is an attractive alternative, eliminating the need for ultralow temperatures, reducing storage maintenance costs, and providing logistical flexibility for shipping. Many seeds and anhydrobiotic organisms are able to survive extended periods in a dry state through the accumulation of intracellular sugars and other osmolytes and are capable of returning to normal physiology postrehydration. Using techniques inspired by nature's adaptations, attempts have been made to dehydrate and dry preserve spermatozoa from a variety of species. Most of the anhydrous preservation research performed to date has focused on mouse spermatozoa, with only a small number of studies in nonrodent mammalian species. There is a significant difference between sperm function in rodent and nonrodent mammalian species with respect to centrosomal inheritance. Studies focused on reproductive technologies have demonstrated that in nonrodent species, the centrosome must be preserved to maintain sperm function as the spermatozoon centrosome contributes the dominant nucleating seed, consisting of the proximal centriole surrounded by pericentriolar components, onto which the oocyte's centrosomal material is assembled. Preservation techniques used for mouse sperm may therefore not necessarily be applicable to nonrodent spermatozoa. The range of technologies used to dehydrate sperm and the effect of processing and storage conditions on fertilization and embryogenesis using dried sperm are reviewed in the context of reproductive physiology and cellular morphology in different species.

Comparison of intracytoplasmic sperm injection with testicular spermatozoa success in infertile men with obstructive and non-obstructive azoospermia; a retrospective analysis

The aim of this study was to compare the outcome of intracytoplasmic sperm injection (ICSI) and embryo transfer between couples with infertility due to male non-obstructive azoospermia (NOA) and obstructive azoospermia (OA). A retrospective analysis of 234 couples with azoospermia who were treated by ICSI and embryo transfer between January 2007 and October 2010 was performed. There were 61 couples in NOA group and 173 couples in OA group. Fertilization rates, pregnancy and clinical pregnancy rates were the main outcome measures. The number of retrieved mature oocytes, injected oocytes, metaphase II (MII) oocytes, two distinct pronuclei oocytes, cleavage embryos and embryos transferred was not significantly different between the groups. The fertilization rate was significantly lower in NOA group when compared to OA group (56.2 vs. 66.7%, respectively; p = 0.013) and the pregnancy rate was significantly lower in NOA group than OA group (36.1 vs. 50.9%, respectively; p = 0.046). The clinical pregnancy rates were not statistically different between the patients with NOA and OA azoospermia groups (24.6 vs. 36.4%, respectively; p = 0.09). This study suggests that ICSI and embryo transfer together with testicular sperm extraction results in statistically significant lower fertilization and pregnancy rates in men with NOA when compared to men with OA.

Fertilisation of cryopreserved sperm and unfertilised quail ovum by intracytoplasmic sperm injection

Intracytoplasmic sperm injection (ICSI) is an important technique in animal biotechnology for animal cloning and conservation of genetic resources, but has been a challenge for avian species. In the present study, we investigated the ability of cryopreserved quail spermatozoa to achieve fertilisation and embryo development. Female quail were killed 70–120 min after previous oviposition to collect unfertilised oocytes from the oviduct. Fresh or cryopreserved–thawed spermatozoa were injected into the cytoplasm of unfertilised oocytes, and the manipulated oocytes were incubated in quail surrogate eggshells. Injection of fresh spermatozoa supplemented with inositol 1,4,5-trisphosphate (IP3) resulted in a significantly increased rate of embryo development compared with injection of fresh spermatozoa alone (90% vs 13%, respectively). Although >80% of embryos stopped cell division and development before Hamburger and Hamilton (HH) Stage 3, approximately 15% of embryos from the fresh sperm injection developed to past HH Stage 4, and one embryo survived up to HH Stage 39 (11 days of incubation). In the case of cryopreserved spermatozoa, the embryo development rate was 30% after ICSI, and this increased significantly to 74% with IP3 supplementation. In conclusion, cryopreserved spermatozoa combined with ICSI followed by surrogate eggshell culture can develop quail embryos.

Does sperm origin affect embryo morphokinetic parameters?

PURPOSE

The purpose of our study was to use time-lapse in order to evaluate the impact of sperm origin (fresh ejaculate or surgically retrieved) on embryo morphokinetic parameters and clinical outcome in intracytoplasmic sperm injection (ICSI) cycles.

METHODS

This retrospective monocentric study was conducted in 485 unselected couples undergoing 604 ICSI cycles with embryo culture in the Embryoscope®. Among them, 445 couples underwent ICSI cycle with fresh ejaculated sperm and 40 with surgically retrieved sperm (26 with testicular sperm and 14 with epididymal sperm). Embryo morphokinetic parameters and clinical cycle outcome were compared between fresh ejaculated sperm and surgically retrieved sperm. A subgroup analysis was also conducted between testicular and epididymal sperm ICSI cycles.

RESULTS

Clinical outcome was comparable between groups according to sperm origin. Although most early morphokinetic parameters were comparable between ejaculated and surgical sperm groups, a few parameters were significantly different between both groups, but with a considerable overlap in their distribution. Late cellular events occurred significantly later in the surgical sperm group than in the ejaculated sperm group.

CONCLUSIONS

Morphokinetic analysis did not allow us to identify clinically relevant differences between fresh ejaculate and surgically retrieved sperm groups. Further studies are needed, especially concerning the relationship between sperm origin and late morphokinetic parameters, such as blastocyst development.

Pregnancy outcome after ICSI with thawed testicular sperm from men with non-obstructive azoospermia compared to ICSI with ejaculated sperm from men with severe oligoasthenoteratozoospermia and IVF with normal ejaculated sperm

The aim of the study was to evaluate the clinical pregnancy outcomes, fetal complications and malformation rate of intracytoplasmic injection of thawed cryopreseverd sperm extracted by testicular aspiration from men with non-obstructive azoospermia (NOA) compared with intracytoplasmic injection of fresh ejaculated sperm from men with severe oligoteratoasthenozoospermia (OTA) and standard in vitro fertilization using ejaculated sperm from normospermic men. The mean oocyte fertilization rate was significantly lowest for ICSI with testicular aspirated sperm (NOA group). However, there was no significant difference among the three groups in pregnancy outcomes, namely rates of spontaneous abortion, biochemical pregnancy, extrauterine pregnancy, singleton multifetal pregnancy, preterm delivery before 36 weeks' gestation, maternal complications, transfer to the neonatal intensive care unit, intrauterine growth restriction or fetal malformations. These results suggest that despite some earlier findings that intracytoplasmic injection of aspirated sperm from men with NOA is associated with lower fertilization rates and embryo quality, the pregnancy and immediate neonatal outcomes may be unaffected.

Effects of ascorbic acid on sperm motility, viability, acrosome reaction and DNA integrity in teratozoospermic samples

BACKGROUND

Oxidative stress in teratozoospermic semen samples caused poor assisted reproductive techniques (ART) outcomes. Among antioxidants, ascorbic acid is a naturally occurring free radical scavenger and as such its presence assists various other mechanisms in decreasing numerous disruptive free radical processes.

OBJECTIVE

The main goal of this study was to evaluate potential protective effects of ascorbic acid supplementation during in vitro culture of teratozoospermic specimens.

MATERIALS AND METHODS

Teratozoospermic semen samples that collected from 15 volunteers were processed, centrifuged and incubated at 37(o)C until sperm swimmed-up. Supernatant was divided into four groups and incubated at 37(o)C for one hour under different experimental conditions: Control, 10 µm A23187, 600µm ascorbic acid and 10 µm A23187+600 µm ascorbic acid. After incubation sperm motility, viability, acrosome reaction, DNA damage and malondialdehyde levels were evaluated.

RESULTS

Our results indicated that after one hour incubation, ascorbic acid significantly reduced malondialdehyde level in ascorbic acid group (1.4±0.11 nmol/ml) compared to control group (1.58±0.13 nmol/ml) (p<0.001). At the end of incubation, progressive motility and viability in ascorbic acid group (64.5±8.8% and 80.3±6.4%, respectively) were significantly (p<0.05 and p<0.001, respectively) higher than the control group (54.5±6.8% and 70.9±7.3%, respectively). A23187 significantly (p<0.0001) increased acrosome reaction in A23187 group (37.3±5.6%) compared to control group (8.5±3.2%) and this effect of A23187 attenuated by ascorbic acid in ascorbic acid+A23187 group (17.2±4.4%). DNA fragmentation in ascorbic acid group (20±4.1%) was significantly (p<0.001) lower than controls (28.9±4.6%).

CONCLUSION

In vitro ascorbic acid supplementation during teratozoospermic semen processing for ART could protect teratozoospermic specimens against oxidative stress, and it could improve ART outcome.

Factors influencing intracytoplasmic sperm injection (ICSI) outcome in men with azoospermia

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: The management of patients with non-obstructive azoospermia (NOA) and some cases of obstructive azoospermia involves testicular sperm extraction (TESE or micro-dissection TESE) combined with intracytoplasmic sperm injection (ICSI). Several studies have investigated the effect of the male age, the cause of azoospermia, testicular histopathology, the type of sperm used, and the use of pentoxyphilline, on the ICSI cycle outcome in men with azoospermia. The present study showed that none of these factors influenced the ICSI outcome in men with azoospermia, thus once sperm is found in an azoospermic male, no other male factor seems to influence the ICSI outcome. To our knowledge this is the first study to comment on the outcome of ICSI in men with NOA based on testicular histopathology.

OBJECTIVES

To access the effect of: male age, the cause of azoospermia (obstructive azoospermia vs non-obstructive azoospermia [NOA]), testicular histopathology, the type of sperm used (fresh vs frozen-thawed), and the use of pentoxyphilline on the intracytoplasmic sperm injection (ICSI) cycle outcome in men with azoospermia. To our knowledge this is the first study to comment on the outcome of ICSI in men with NOA based on testicular histopathology.

PATIENTS AND METHODS

A retrospective analysis of 137 testicular sperm extraction-ICSI cycles performed between 2001-2010, involving 103 men with azoospermia, with 26 couples having repeat cycles.

RESULTS

Analysis of the results did not show any statistically significant differences in the fertilization, embryo cleavage, clinical pregnancy, live birth and miscarriage rates in relation to the male age, cuase of azoospermia, testicular histopathology, type of sperm used and the use of pentoxyphilline.

CONCLUSION

Once sperm is found in a man with azoospermia, no other male factor seems to influence the ICSI outcome.

Cryopreservation of individually selected sperm: methodology and case report of a clinical pregnancy

OBJECTIVE

To describe a new technique for freezing individually isolated spermatazoa from testicular biopsies, epididymal aspirates and oligospermic semen samples

METHODS

Samples were evaluated for the presence of motile sperm before cryopreservation. Motile or twitching sperm were isolated with an ICSI needle for single sperm cryopreservation. Selected sperm were loaded on the High Security Straw (HSV; Irvine Scientific; Irvine,CA), in ~0.5 µl of fluid to facilitate recovery. The sample was also frozen using conventional methodology in cryovials (100-1000 µl aliquots). In both freezing techniques, the samples were slow cooled. Test-yolk buffer-glycerol (Irvine) was used as the cryoprotectant. Test-thaws were performed to assess sperm recovery and motility.

RESULTS

Six men with azoospermia had single sperm cryopreservation, as well as freezing aliquots of their testicular or epididymal sperm in traditional cryovials. In addition, two men with oligospermia also had individual sperm selected and frozen. In all 8 cases, the ~0.5 µl of fluid containing sperm was quite easily unloaded from the HSV straw during thawing. The percent sperm recovery ranged from 33% to 100%. Motility was evident in all but one sample. In six cases, the sperm were used for intracytoplasmic sperm injection of mature oocytes. Fertilization occurred in all but one case. In this study, we report the first clinical pregnancy with this technique. This pregnancy was remarkable in that a single motile sperm identified and selected in the initial testicular preparation was successfully frozen. We were able to subsequently recover this sperm, fertilize an oocyte and the resultant embryo gave rise to a live birth. The methodology described in this preliminary report offers a new modality for sequestering small numbers of sperm. It may be particularly useful in cases involving severe impairment of spermatogenesis, where extensive screening may be necessary to find a few viable sperm.