Development and current applications of assisted fertilization

Oligoasthenospermia is correlated with increased preeclampsia incidence in subfertile couples undergoing in vitro fertilization and embryo transfer: a secondary analysis of a randomized clinical trial

OBJECTIVE

To evaluate whether intergroup differences in the risk of maternal pregnancy complications after in vitro fertilization (IVF) vary with male factor.

DESIGN

A post hoc exploratory secondary analysis of data from a multicenter, randomized, controlled noninferiority trial (NCT03118141).

SETTING

Academic fertility centers.

PATIENT(S)

A total of 1,131 subfertile women with complete recording of their male partner's semen parameters during the trial were enrolled. All participants underwent intracytoplasmic sperm injection followed by frozen embryo transfer (ET) as part of their assisted reproductive technology treatment protocol.

INTERVENTION(S)

Women were divided into the oligoasthenospermia (n = 405) and normospermia (n = 726) groups according to the quality of male sperm.

MAIN OUTCOME MEASURE(S)

Pregnancy complications, principally including the incidence of preeclampsia.

RESULT(S)

Notably, we found that the risk of maternal preeclampsia was significantly higher in the oligoasthenospermia group than in the normospermia group. After adjustments for confounding factors by multivariate logistic regression analysis, the incidence of preeclampsia in the oligoasthenospermia group was still significantly higher than that in the normospermia group (6.55% vs. 3.60%; odds ratio, 0.529; 95% confidence interval, 0.282-0.992). However, there were no significant differences in terms of embryo quality, cumulative live birth rate, other pregnancy complications, or neonatal outcomes between the 2 groups.

CONCLUSION(S)

Oligoasthenospermia was associated with a higher risk of maternal preeclampsia in subfertile couples undergoing IVF-ET treatment. In clinical practice, it is essential to thoroughly evaluate the sperm quality and quantity of male partners before IVF-ET. Further research is needed to establish the causal relationships between semen quality and adverse pregnancy complications, particularly preeclampsia, and explore potential interventions.

A comprehensive investigation of human endogenous retroviral syncytin proteins and their receptors in men with normozoospermia and impaired semen quality

PURPOSE

The study aims to investigate first the presence of Syncytin 2 and its receptor, MFSD2, in human sperm, and second whether the expressions of Syncytin 1, Syncytin 2, and their receptors, SLC1A5 and MFSD2, differ between normozoospermic, asthenozoospermic, oligozoospermic, and oligoasthenozoospermic human sperm samples.

METHODS

The localization patterns and expression levels of syncytins and their receptors were evaluated in normozoospermic (concentration = 88.9 ± 5.5 × 10⁶, motility = 79.2 ± 3.15%, n = 30), asthenozoospermic (concentration = 51.7 ± 7.18 × 10⁶, motility = 24.0 ± 3.12%, n = 15), mild oligozoospermic (concentration = 13.5 ± 2.17 × 10⁶, motility = 72.1 ± 6.5%, n = 15), moderate oligozoospermic (concentration = 8.4 ± 3.21 × 10⁶, motility = 65.1 ± 8.9%, n = 15), severe oligozoospermic (concentration = 2.1 ± 1.01 × 10⁶, motility = 67.5 ± 3.2%, n = 15), and oligoasthenozoospermic (concentration = 5.5 ± 3.21 × 10⁶, motility = 18.5 ± 1.2%, n = 15) samples by immunofluorescence staining and western blot.

RESULTS

Syncytins and their receptors visualized by immunofluorescence showed similar staining patterns with slight staining of the tail in all spermatozoa regardless of normozoospermia, asthenozoospermia, oligozoospermia, or oligoasthenozoospermia. The localization patterns were categorized as equatorial segment, midpiece region, acrosome, and post-acrosomal areas. The combined staining patterns were also detected as acrosomal cap plus post acrosomal region, the midpiece plus equatorial segment, and midpiece plus acrosomal region. However, some sperm cells were categorized as non-stained. Both syncytin proteins were most intensely localized in the midpiece region, while their receptors were predominantly present in the midpiece plus acrosomal region. Conspicuously, syncytins and their receptors showed decreased expression in asthenozospermic, oligozoospermic, and oligoasthenozoospermic samples compared to normozoospermic samples.

CONCLUSION

The expression patterns of HERV-derived syncytins and their receptors were identical regardless of the spermatozoa in men with normozoospermia versus impaired semen quality. Further, asthenozoospermia, oligozoospermia, and oligoasthenozoospermia as male fertility issues are associated with decreased expression of both syncytins and their receptors.

The practice of intracytoplasmic sperm injection in Jordan: A clinical outcome study

Objective

The lack of appropriate guidelines and justified practice in most developing countries is a serious limitation to efforts to qualify the services provided. In this paper, we evaluate and assess the clinical practice of an assisted reproductive technique of intracytoplasmic sperm injection (ICSI) in Jordan.

Methods

Retrospectively, we identified women who achieved a successful pregnancy by ICSI over a period of ten years. Information related to the ICSI procedure, foetus abnormalities, maternal complications and delivery outcomes were included. A control group of normal pregnancies were incorporated.

Results

In total, 291 cases were included as successful cases of ICSI with a success rate of 14.1%. For the control group, 466 pregnant women with normal pregnancies were included. No statistical difference was observed between both groups in foetus malformation. In normal pregnancy women, 42.1% delivered through caesarean section (CS) while 87.6% of ICSI patients underwent CS. Women with ICSI had significantly higher rates of multiple gestations, and their neonates were lower in birthweight. Women in the ICSI group tended to deliver females compared to the control group. Pregnancy-related hypertension was more commonly reported in the normal pregnancy group, while gestational diabetes, antepartum haemorrhage and preterm labour were more common in ICSI group.

Conclusion

Services for the management of infertility are increasing in the Middle East. The clinical outcomes in Jordan is approaching that of other developed regions, although the success rate is lower than in other regions. Further studies and efforts should be carried out to maximize effective and successful practice in such low-income areas.

•

The practice of ICSI needs to be justified in the developing countries.

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The success rate of ICSI is low with higher rates of CS and multiple gestation.

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Neonates for women with ICSI are born with lower birth weight.

Reproductive outcomes with donor sperm in couples with severe male-factor infertility after intracytoplasmic sperm injection failures

PURPOSE

To evaluate reproductive outcomes of artificial insemination and IVF with donor sperm (AID or IVF-D) for male-factor couples with a history of unsuccessful ICSI attempt.

METHODS

This retrospective cohort includes couples with severe male-factor infertility who failed ICSI treatment, and subsequently underwent semen donation treatment. We report the following outcomes: (1) live birth rates in AID and IVF-D treatment for couples with severe male infertility factors and prior ICSI failures; (2) paternal impact on embryo development of the same oocyte cohort; (3) prognostic factors in obtaining a live birth with donor semen.

RESULTS

Of 92 women with failed ICSI cycles (26 with multiple attempts), 45 couples underwent AID treatment. Live birth rate per cycle of AID was 18.9%. Fifty-three patients underwent IVF-D including 6 couples who previously did not conceive with AID. Embryological outcomes including fertilization, viable cleavage embryos, and blastocyst formation rates were significantly lower in ICSI cycles with partner sperm compared with IVF-D (P < 0.01). Logistic regression analysis showed that female age and the severity of spermatogenetic disorder are prognostic factors in obtaining a live birth with donated sperm.

CONCLUSION

Couples with severe male infertility factor (azoospermia or extreme oligoasthenospermia) and a history of unsuccessful ICSI cycles benefit from treating with donor sperm. ICSI fertilization, embryo viability, and progression of the embryo to the blastocyst stage are significantly deteriorated by semen parameters. The prognostic factors identified may help couples plan their treatment and prepare for their parenthood journey.

Use of mini-incision microdissection testicular sperm extraction in men with cryptozoospermia and non-obstructive azoospermia

INTRODUCTION

Microdissection testicular sperm extraction (micro-TESE) is a procedure commonly utilized to harvest spermatozoa in severe male factor infertility. We have developed a technique involving a mini tunica albuginea incision with superficial tissue dissection (mini-incision micro-TESE). The modification is designed to reduce potential tissue injury, and we studied its effectiveness to harvest spermatozoa in men with cryptozoospermia and non-obstructive azoospermia.

MATERIALS AND METHODS

We performed a retrospective analysis of 103 infertile men with NOA and cryptozoospermia who underwent a mini-incision micro-TESE between March 2015 and August 2018 at the OVO fertility clinic. We consider the mini-incision micro-TESE procedure successful when at least five spermatozoa are identified in the micro-biopsies obtained from the superficial tissue exposed by the 1-cm mini-incision. If no spermatozoa are identified through the mini-incision, we can easily extend the incision to the standard micro-TESE.

RESULTS

The mini-incision procedure allowed for successful recovery of spermatozoa (intra-operative recovery of ≥ 5 spermatozoa) in 58% of men with cryptozoospermia and 25.6% of men with NOA. Overall, a successful sperm retrieval (with conversion to conventional micro-TESE if mini-incision was not successful) was achieved in 89% of men with cryptozoospermia and 48% of men with NOA. A successful mini-incision micro-TESE was associated with a significantly lower number of biopsies than conventional micro-TESE (8.8 vs 24.2, P < .0001). Moreover, in men undergoing a redo micro-TESE after a previously successful micro-TESE, 64% (9/14) had spermatozoa found and 21% (3/14) of these men only required a mini-incision micro-TESE.

CONCLUSION

Our data suggest that mini-incision micro-TESE is a useful approach in men undergoing micro-TESE, allowing for a shorter incision and a high sperm retrieval rate in men with cryptozoospermia. Furthermore, the findings of our study offer insight into the distribution of spermatogenesis in men with cryptozoospermia and NOA.

Effect of paternal age on intracytoplasmic sperm injection outcomes in cryptozoospermic men: Ejaculated or testicular sperm?

It is not clear whether age has any influence on the outcomes for sperm used for assisted reproductive technology in cryptozoospermic men. We evaluated intracytoplasmic sperm injection (ICSI) outcomes using ejaculated or testicular sperm in men with cryptozoospermia from different paternal age ranges.We conducted a retrospective observational study of 35 men with cryptozoospermia who underwent ICSI from 2010 to 2018. They were classified into 2 groups based on male age, namely < 35 years and ≥ 35 years. Each group was further divided into 2 subgroups according to the origin of sperm (ejaculated or testicular).In the <35 years group, the normal fertilization and high-quality embryo rates for ejaculated sperm were significantly higher than with testicular sperm (74.7% vs. 62.4%, P = .02; 50.5% vs. 36.6%, P = .03, respectively). However, in the ≥35 years group, the high-quality embryo and clinical pregnancy rates were significantly lower in the ejaculated sperm subgroup than in the testicular sperm subgroup (26.2% vs. 63%, P = .002; 12.5% vs. 71.4%, P = .04, respectively).This study indicates that ICSI should be performed as soon as possible for men with cryptozoospermia. When the paternal age ≥35 years, testicular sperm should be used for ICSI, as this offers better high-quality embryo and clinical pregnancy rates.

Genetic and epigenetic profiling of the infertile male

Evaluation of reproductive quality of spermatozoa by standard semen analysis is often inadequate to predict ART outcome. Men may be prone to meiotic error and have higher proportion of spermatozoa with fragmented chromatin, capable of affecting the conceptus' health. In men with unexplained infertility, supplementary tests may be pivotal to gain insight into the paternal contribution to the zygotic genome. A total of 113 consenting men were included in the study, with an additional 5 donor specimens used as control. Among study participants, 87 were screened for sperm aneuploidy by fluorescent in situ hybridization (FISH) and ranked according to their increasing age. A total of 18 men were assessed by whole exome sequencing and categorized according to their reproductive outcome as either fertile or infertile. Another set of men (n = 13) had their gene expression analyzed by RNA-seq and were profiled according to their reproductive capacity. FISH revealed that the average aneuploidy rate was highest for men over-55 age group (9.6%), while men >55 had the highest average disomy for chromosomes 17(1.2%) and 18(1.3%). ART results for the entire cohort comprised 157 cycles, stratified by paternal age. The youngest age group (25-30 years) had a fertilization rate of 87.7% which decreased to 46.0% in the >55 age group. Clinical pregnancy rate was highest in the 25-30yr group (80.0%) while no pregnancies were attained in the >55 age groups. Pregnancy loss was characterized by a steadily increasing trend, highest in the 51-55 age group (50.0%). NGS was performed on a cohort of patients classified as having recurrent pregnancy loss. This cohort was classified as the infertile group (n = 10) and was compared to a control group (n = 8) consisting of patients successfully treated by ART. Eight couples in 17 ICSI cycles achieved a clinical pregnancy rate of 82.4% while 10 infertile couples treated in 21 cycles achieved a pregnancy rate of 23.8%, all resulting in pregnancy loss. DNA-sequencing on spermatozoa from these patients yielded overall aneuploidy of 4.0% for fertile and 8.6% for the infertile group (P<0.00001). In the infertile cohort, we identified 17 genes with the highest mutation rate, engaged in key roles of gametogenesis, fertilization and embryo development. RNA-seq was performed on patients (n = 13) with normal semen analyses. Five men unable to attain a pregnancy after ART were categorized as the infertile group, while 8 men who successfully sustained a pregnancy were established as the fertile control. Analysis resulted in 86 differentially expressed genes (P<0.001). Of them, 24 genes were overexpressed and 62 were under-expressed in the infertile cohort. DNA repair genes (APLF, CYB5R4, ERCC4 and TNRFSF21) and apoptosis-modulating genes (MORC1, PIWIL1 and ZFAND6) were remarkably under-expressed (P<0.001). Sperm aneuploidy assessment supported by information on gene mutations may indicate subtle dysfunctions of the spermatozoon. Furthermore, by querying noncoding RNA we may gather knowledge on embryo developmental competence of spermatozoa, providing crucial information on the etiology of unexplained infertility of the infertile male.

Assisted Reproduction is Not Associated with Increased Risk of Congenital Head and Neck Defects

This abstract was presented at the American Academy of Otolaryngology-Head and Neck Surgery Annual Meeting, Orlando, FL, September 2014 with the abstract published (Neumann C, Thompson D, and Sidman J; Assisted reproduction is not associated with increased risk of head and neck defects; Otolaryngology-Head and Neck Surgery; Vol 151, Issue 1, supplement, 2014). Objectives - Compare the rate of head and neck anomalies between children conceived via artificial reproductive technology (ART) versus those conceived via natural methods. - Determine the risk of congenital head and neck abnormalities associated with ART. Study design A retrospective chart review cross-sectional study from 2004-2014 of all patients admitted to the neonatal intensive care unit (NICU) at a tertiary pediatric hospital. Results A total of 14,857 charts were examined; 2,288 patients were conceived via ART, while 12,569 patients were conceived via natural methods. There were 8,022 males and 6,637 females. There were 40 patients born with defects via ART, while there were 681 patients born with defects via natural conception. The total occurrence of congenital malformations was higher for patients conceived naturally versus those conceived with artificial reproduction (5.41% vs. 1.74%). The odds ratio was 0.31 with a 95% CI of 0.23 to 0.43 and a P-value of < 0.0001; the relative risk of having any one of the head and neck defects with ART was 1.04 with a 95% CI of 1.03 to 1.05 and a P-value < 0.0001. Conclusion There appears to be no increased risk of congenital head and neck defects in children conceived via ART versus those conceived naturally.

Intracytoplasmic sperm injection: state of the art in humans

Among infertile couples, 25% involve both male and female factors, while male factor alone accounts for another 25% due to oligo-, astheno-, teratozoospermia, a combination of the three, or even a complete absence of sperm cells in the ejaculate and can lead to a poor prognosis even with the help of assisted reproductive technology (ART). Intracytoplasmic sperm injection (ICSI) has been with us now for a quarter of a century and in spite of the controversy generated since its inception, it remains in the forefront of the techniques utilized in ART. The development of ICSI in 1992 has drastically decreased the impact of male factor, resulting in millions of pregnancies worldwide for couples who, without ICSI, would have had little chance of having their own biological child. This review focuses on the state of the art of ICSI regarding utility of bioassays that evaluate male factor infertility beyond the standard semen analysis and describes the current application and advances in regard to ICSI, particularly the genetic and epigenetic characteristics of spermatozoa and their impact on reproductive outcome.

Effect of sperm pretreatment with glutathione and membrane destabilizing agents lysolecithin and Triton X-100, on the efficiency of bovine intracytoplasmic sperm injection

Intracytoplasmic sperm injection (ICSI) is an assisted reproduction tool with several applications. Its effectiveness in bovines is lower than that in other species, mainly because of difficulties in the decondensation of the sperm nucleus after injection, and the presence of the acrosome and the plasma membrane which remain intact in this procedure. In this study, we assessed the effect of lysolecithin (LL) and Triton X-100 (TX), in combination with glutathione (GSH) as sperm pretreatments prior to ICSI. The GSH-LL and GSH-TX groups showed 0% of spermatozoa with intact membrane (SYBR 14+/PI), in comparison with the control (63.3%) and GSH (65.7%) groups. The proportions of spermatozoa with damaged acrosome membrane in the GSH-LL, GSH-TX, GSH and control groups were 46%, 35.9%, 10.5% and 7.5%, respectively. Sperm chromatin decondensation analysis showed that the groups incubated for 3 hr with GSH presented greater decondensation (p < .05). Although fertilization was improved in all treatment groups evaluated, no differences were observed in the cleavage rate 72 hr after activation in the GSH (73.7%), GSH-LL (80.2%) and GSH-TX (77.8%) groups compared to the control (66.3%), neither in the blastocyst rate on day 8 (24.0%, 26.2%, 27.1% and 28.4% for the control, GSH, GSH-LL and GSH-TX groups, respectively). No differences were also observed in the total number of cells in all groups. In conclusion, although these sperm treatments promoted nuclear decondensation and induced plasma membrane disruption, these effects were not sufficient to improve bovine embryonic development after ICSI.

Changes in Sperm Motility and Capacitation Induce Chromosomal Aberration of the Bovine Embryo following Intracytoplasmic Sperm Injection

Intracytoplasmic sperm injection (ICSI) has become the method of choice to treat human male infertility. One of the outstanding problems associated with this technique is our current lack of knowledge concerning the effect of sperm capacitation and motility upon the subsequent development of oocytes following ICSI. In the present study, we first examined the capacitation state of sperm exhibiting normal motility, along with sperm that had been activated, and examined the effect of reactive oxygen species (ROS) produced by these sperm types upon embryogenesis following bovine in vitro fertilization (IVF) and ICSI. Data showed that activated sperm reduced the chromosomal integrity of IVF/ICSI embryos at the blastocyst stage, while capacitated sperm produced ROS in capacitation media. Secondly, we treated sperm with carbonyl cyanide m-chlorophenyl hydrazine (CCCP), a chemical known to uncouple cell respiration within the mitochondria, and investigated the effect of this treatment upon blastocyst formation and chromosomal integrity at the blastocyst stage. Activated sperm in which the mitochondria had been treated with CCCP reduced levels of chromosomal aberration at the blastocyst stage following ICSI, by reducing mitochondrial activity in activated sperm. In conclusion, these findings suggest that capacitated sperm exhibiting activated motility induced chromosomal aberration during development to the blastocyst stage following ICSI. The injection of sperm exhibiting normal motility, or activated sperm in which mitochondrial activity had been reduced, improved the quality of ICSI-derived embryos. Therefore, the selection of sperm exhibiting progressive motility may not always be better for early embryo development and fetal growth following human ICSI, and that the use of a bovine model may contribute to a deeper understanding of sperm selection for human ICSI embryo development.

In Vivo Culture System Using the INVOcell Device Shows Similar Pregnancy and Implantation Rates to Those Obtained from In Vivo Culture System in ICSI Procedures

CAPSULE

Clinical outcomes using INVOcell device with ICSI.

OBJECTIVE

Intravaginal culture of oocytes (INVO) procedure is an intravaginal culture system that utilizes the INVOcell device in which the fertilization and embryo culture occur. In this procedure, the vaginal cavity serves as an incubator for oocyte fertilization and early embryonic development. The objective of this study was to evaluate the clinical outcomes of this intravaginal culture system in intracytoplasmic sperm injection (ICSI).

METHODS

A total of 24 cycles INVO-ICSI (study group) and 74 cycles of ICSI (control group) were included in the study. The cleaved oocytes at day 3/total injected oocytes, embryo quality, pregnancy rate (PR), implantation rate (IR), and miscarriage rate (MR) were compared between both groups.

RESULTS

At day 3, there was no difference in the cleaved oocyte rate (78.7 and 76.1%) and embryo quality (77 and 86.8%) for the study and control groups, respectively. In the study group, more embryos were significantly transferred compared to the control group (2.63 ± 0.58 versus 1.93 ± 0.25; P < 0.05). PRs, IRs, and MRs were similar for the study group compared with the control group (PR: 54.2% versus 58.1%; IR: 31.7% versus 33.6%; MR: 7.7% versus 20.9%).

CONCLUSIONS

Good PR and IR can be obtained using the INVOcell device, and the INVO-ICSI procedure can be considered as an alternative option to infertile patients.

Variability between the follicular steroid hormone levels in different follicles of the same patient and between patients

CONTEXT

There is disagreement as to whether the concentration of a substance in follicular fluid is related to the quality of the follicle as a possible reflection of the oocyte quality or whether this concentration is related to the clinical characteristics of the patient.

AIM

To establish the variability of steroid hormone levels in follicular fluids from different follicles of the same patient and between patients.

SETTINGS AND DESIGN

Prospective cohort study.

MATERIALS AND METHODS

In 31 patients who underwent intracytoplasmic sperm injection it was performed an ultrasound guided aspiration of follicular fluid of the first two mature follicles from each ovary. Chemiluminescent microparticle immunoassays were performed to determine the levels of estradiol, progesterone, testosterone, and dehydroepiandrosterone sulfate (DHEA-S).

STATISTICAL ANALYSIS

Unconditional mixed model.

RESULTS

Variation in estradiol levels between follicles in the same patient was approximately twice the variation between subjects (P = 0.05). In the case of progesterone, the intra-subject variation was similar to the inter-subject variation (P = 0.006). The testosterone levels had a slightly smaller intra-subject variation than inter-subject variation (P = 0.002), and the intra-subject variation in DHEA-S levels was approximately one-fifth of the inter-subject variation (P = 0.0003).

CONCLUSIONS

The variations in the levels of follicular progesterone and testosterone were similar between patients and between a given patient's follicles; however, the estradiol levels variability was higher among different follicles. The amount of follicular estradiol may be considered a selection tool between the follicles of a given patient.

Intracytoplasmic sperm injection (ICSI) in extreme cases of male infertility

INTRODUCTION

Severely compromised spermatogenesis typical of men with virtual azoospermia or non-obstructive azoospermia requires an extreme search for spermatozoa. Our goal was to evaluate the usefulness of a meticulous search carried out in ejaculated or surgically retrieved specimens in achieving pre- and post-implantation embryo development.

PATIENTS AND METHODS

In a retrospective cohort study carried out in an academic institution, intracytoplasmic sperm injection (ICSI) outcomes were reviewed as a function of length of microscopic sperm search in ejaculated and surgically retrieved specimens. Couples whose male partner presented with either virtual or non-obstructive azoospermia were treated by ICSI and categorized according to the time spent in identifying and retrieving enough spermatozoa to inject all the oocyte cohort. Semen parameter, fertilization, pregnancies, deliveries, and child welfare in relation to increasing search time were analyzed and compared.

RESULT(S)

The maternal and paternal ages were comparable in both ejaculated and testicular sperm extraction (TESE) groups along with the oocytes retrieved. The fertilization rates for both ejaculated and TESE progressively decreased with increasing time (P<0.0001). Clinical pregnancies in the ejaculated cohort remained satifactory. In the TESE cohort, there was a decrease in pregnancy rate with increasing time, from 44% to 23%. In a limited number of cases, offspring health was evaluated in both semen sources and appeared reassuring.

CONCLUSION(S)

An extensive and at time exhaustive sperm quest yields kinetically and morphologically impaired spermatozoa without apparent impact on embryo developmental competence. Retrieval of spermatozoa from the seminiferous tubules provided more consistent fertilization and pregnancy outcomes than those retrieved from the ejaculate. A trend indicated that pregnancy rate decreased as search time increased in the TESE group. The utilization of the scarce and unselected spermatozoa did not obviously impair embryo development or cause post-implantation errors.

Ovum pick up, intracytoplasmic sperm injection and somatic cell nuclear transfer in cattle, buffalo and horses: from the research laboratory to clinical practice

Assisted reproductive techniques developed for cattle in the last 25 years, like ovum pick up (OPU), intracytoplasmic sperm injection (ICSI), and somatic cell nuclear transfer, have been transferred and adapted to buffalo and horses. The successful clinical applications of these techniques require both the clinical skills specific to each animal species and an experienced laboratory team to support the in vitro phase of the work. In cattle, OPU can be considered a consolidated technology that is rapidly outpacing conventional superovulation for embryo transfer. In buffalo, OPU represents the only possibility for embryo production to advance the implementation of embryo-based biotechnologies in that industry, although it is still mainly in the developmental phase. In the horse, OPU is now an established procedure for breeding from infertile and sporting mares throughout the year. It requires ICSI that in the horse, contrary to what happens in cattle and buffalo, is very efficient and the only option because conventional IVF does not work. Somatic cell nuclear transfer is destined to fill a very small niche for generating animals of extremely high commercial value. The efficiency is low, but because normal animals can be generated it is likely that advancing our knowledge in that field might improve the technology and reduce its cost.

Development block of golden hamster ICSI embryos is associated with decreased expression of HDAC1, HSPA1A and MYC

We have investigated the mechanism for embryo development block in vitro and to improve the development rate of golden hamster embryos in vitro. Intracytoplasmic sperm injection (ICSI) technique was used to produce golden hamster ICSI embryos. The changes in the histone acetylation and the expression of histone deacetylase and related genes were analyzed by immunocytochemical staining and real-time PCR both in golden hamster in vivo embryos and in ICSI embryos. Aged oocytes significantly increased the oocyte spontaneous activation rate. In vitro cultured ICSI embryos suffered from severe development block in M199TE medium. Expression of histone deacetylase 1 (HDAC1) was significantly decreased in the nuclei of the arrested ICSI 2-cell embryos, and its nuclear and cytoplasmic expression pattern was also markedly altered. The acetylation level of H4K5, however, was not significantly changed between golden hamster in vivo embryos and ICSI embryos. HSPA1A and MYC, the marker genes for zygotic genome activation (ZGA), were transcriptionally decreased in arrested ICSI 2-cell embryos. Transcription of HDAC1 was also downregulated in these embryos, whereas the mRNA expression of the proapoptotic gene, BAX, was not changed. These results indicate that the golden hamster ICSI embryo development block during ZGA is associated with decreased nuclear expression and altered expression of HDAC1. HSPA1A, MYC, and HDAC1 mRNA levels, which decrease, resulting in ZGA failure.

Understanding the spermatozoon

The former perception of the spermatozoon as a delivery device of the male genome has been expanded to include a new understanding of the cell's complex role in fertilization. Once the spermatozoon reaches the oocyte, it triggers egg activation and orchestrates the stages of pre- and post-fertilization in a preprogrammed pattern while tapping the oocyte's resources in an effort to generate a new life.

Understanding fertilization through intracytoplasmic sperm injection (ICSI)

Since the establishment of in vitro fertilization, it became evident that almost half of the couples failed to achieve fertilization and this phenomenon was attributed to a male gamete dysfunction. The adoption of assisted fertilization techniques particularly ICSI has been able to alleviate male factor infertility by granting the consistent ability of a viable spermatozoon to activate an oocyte. Single sperm injection, by pinpointing the beginning of fertilization, has been an invaluable tool in clarifying the different aspects of early fertilization and syngamy. However, even with ICSI some couples fail to fertilize due to ooplasmic dysmaturity in relation to the achieved nuclear maturation marked by the extrusion of the first polar body. More uncommon are cases where the spermatozoa partially or completely lack the specific oocyte activating factor. In this work, we review the most relevant aspects of fertilization and its failure through assisted reproductive technologies. Attempts at diagnosing and treating clinical fertilization failure are described.

Clinical pregnancy after uterus transplantation

OBJECTIVE

To present the first clinical pregnancy after uterus transplantation.

DESIGN

Case study.

SETTING

Tertiary center.

PATIENT(S)

A 23-year-old Mayer-Rokitansky-Kuster-Hauser syndrome patient with previous vaginal reconstruction and uterus transplantation.

INTERVENTION(S)

Eighteen months after the transplant, the endometrium was prepared for transfer of the thawed embryos.

MAIN OUTCOME MEASURE(S)

Implantation of embryo in an allografted human uterus.

RESULT(S)

The first ET cycle with one day 3 thawed embryo resulted in a biochemical pregnancy. The second ET cycle resulted in a clinical pregnancy confirmed with transvaginal ultrasound visualization of an intrauterine gestational sac with decidualization.

CONCLUSION(S)

We have presented the first clinical pregnancy in a patient with absolute uterine infertility after uterus allotransplantation. Although the real success is the delivery of a healthy near-term baby, this clinical pregnancy is a great step forward and a proof of concept that the implantation phase works.

The next (re)generation of ovarian biology and fertility in women: is current science tomorrow's practice?

Stem cell-based strategies for ovarian regeneration and oocyte production have been proposed as future clinical therapies for treating infertility in women. However, utilization of embryonic stem cells or induced pluripotent stem cells to produce oocytes has had limited success in vitro. A recent report of the isolation and characterization of endogenous oocyte-producing or oogonial stem cells (OSCs) from ovaries of reproductive age women describes the first stable and pure human female germ cell culture model in which a subset of cells appear to initiate and complete meiosis. In addition, purified human OSCs introduced into adult human ovarian cortical tissue generate oocytes that arrest at the diplotene stage of meiosis and successfully recruit granulosa cells to form new primordial follicles. This overview examines the current landscape of in vitro and in vivo gametogenesis from stem cells, with emphasis on generation of human oocytes. Future research objectives for this area of work, as well as potential clinical applications involving the use of human OSCs, are discussed.

Oocyte vitrification does not increase the risk of embryonic aneuploidy or diminish the implantation potential of blastocysts created after intracytoplasmic sperm injection: a novel, paired randomized controlled trial using DNA fingerprinting

OBJECTIVE

To assess the impact of oocyte vitrification on aneuploidy and reproductive potential by comparing vitrified and control oocytes from a single patient within a single cycle and a single fresh transfer.

DESIGN

Paired randomized controlled trial in which each patient's cohort of mature oocytes was divided into two even groups with half undergoing Cryotop vitrification and rapid warming and half serving as controls.

SETTING

Academic center for reproductive medicine.

PATIENT(S)

Forty-four patients with a mean age of 29.9 ± 2.3 years and normal ovarian reserve.

INTERVENTION(S)

Cryotop vitrification of half of mature oocytes. Trophectoderm biopsy with single nucleotide polymorphism microarray analysis for ploidy and DNA fingerprinting.

MAIN OUTCOME MEASURE(S)

Rate of aneuploidy (primary outcome), fertilization, cleavage, blastulation, and implantation in embryos derived from vitrified and control oocytes.

RESULT(S)

A total of 588 mature oocytes were randomized, with 240/294 (81.6%) surviving vitrification. Among surviving vitrified oocytes, there was a lower fertilization rate with intracytoplasmic sperm injection (77.9% vs. 90.5%; relative risk [RR], 0.86; 95% confidence interval [CI], 0.80-0.93), a lower cleavage rate (90.9% vs. 99.2%; RR, 0.92; 95% CI, 0.87-0.96), and a lower usable blastocyst formation rate per two pronuclei (34.8% vs. 50.8%; RR, 0.68; 95% CI, 0.54-0.86). There was no difference in the rate of embryonic aneuploidy (vitrified, 29.1% vs. control, 26.4%). In paired blastocyst transfers, the ongoing pregnancy rate per embryo transferred was similar (vitrified, 53.9% vs. control, 57.7%).

CONCLUSION(S)

Although the IVF process is less efficient after oocyte vitrification, implantation rates are equivalent and there is no increased risk of aneuploidy. Given the lack of other viable options, this study provides great reassurance to patients and clinicians applying oocyte vitrification for fertility preservation.