Relationship between sperm DNA damage, induced acrosome reaction and viability in ICSI patients

The DNA damage in human spermatozoa is a relevant predictor of prognosis in male infertility, whereby increased sperm DNA damage impairs the outcomes of artificial reproduction. Theoretically, DNA damage should alter the special cellular functions of human spermatozoa, and lead to diminished acrosome reaction with reduced fertilization rates. Nevertheless, intracytoplasmic sperm injection (ICSI) has been reported to alleviate such negative outcomes due to DNA damage. This study investigated the relationship between DNA fragmentation and acrosome reaction as well as viability in ICSI patients. The study enrolled 42 men undergoing ICSI due to poor sperm parameters. The DNA fragmentation indexes (DFI) were 4-10% in 38% of the cases, and > or = 10% in 19% of the cases. The results of both acrosome reaction and viability assays showed negative correlations with DFI values in all cases and especially in cases with fertilization rates <60% (P < 0.05). However, such correlations were not found in cases with fertilization rates >60%. There were no live deliveries in patients with high DFI levels (>10%). In conclusion, negative correlations were identified between increased DNA damage, and acrosome reaction and/or viability of human spermatozoa, especially in cases with reduced fertilization rates.

Cytokine and hormonal profile in blood serum and follicular fluids during ovarian stimulation with the multidose antagonist or the long agonist protocol

BACKGROUND

The aim of our study was to explore cytokine and hormonal profiles in blood and follicular fluids from normal women stimulated with either the multidose antagonist or the long agonist protocol.

METHODS

Fifty-six patients were stimulated with the multidose antagonist protocol and 12 with the long agonist protocol. Interleukin (IL)-1beta, IL-6, tumour necrosis factor-alpha (TNFalpha), leptin, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), estradiol (E(2)), progesterone and testosterone levels were measured in serum and follicular fluids by immunoassays.

RESULTS

The two treatment groups had similar cytokine concentrations in serum. The intrafollicular concentrations of IL-1beta, IL-6, VEGF and leptin were also similar in the two groups. The concentrations of bFGF in follicular fluids from the antagonist group (169.5 +/- 113.2 ng/ml) were lower than those from the agonist group (249.7 +/- 119.8 ng/ml). bFGF concentrations were correlated with the amount of administered gonadotrophins (R = 0.364, P < 0.01) which was significantly lower in the antagonist group (antagonist group: 2037.7 +/- 725.8 IU; agonist group: 2836.4 +/- 1163.5 IU).

CONCLUSIONS

Normal women stimulated with either the multidose antagonist or the long agonist protocol generally have similar cytokine profiles in serum and follicular fluids. The intrafollicular levels of bFGF tend to be lower in antagonist cycles because of the lower amount of administered gonadotrophins.

Comet assay of cumulus cells and spermatozoa DNA status, and the relationship to oocyte fertilization and embryo quality following ICSI

It has been postulated that apoptosis may affect cumulus cell and sperm DNA integrity, and therefore influence the outcome of assisted reproductive techniques. This study investigates apoptotic levels in both cumulus cells and spermatozoa, and their relationship with fertilization and embryo quality after intracytoplasmic sperm injection (ICSI). The neutral comet assay was performed on cumulus cells and semen samples from 55 couples with male factor infertility undergoing ICSI treatment. Cells were fixed in agarose on comet assay slides, lysed in a neutral buffer and submitted to electrophoresis. The cells were stained with SYBR green fluorescent dye, which binds to double-stranded DNA and upon excitation emits light. Analysis showed that there was no correlation between apoptosis levels and the outcome of ICSI (fertilization and embryo quality).

IGF-I and epidermal growth factor levels in follicular fluid of women undergoing controlled ovarian hyperstimulation using the multidose GnRH-antagonist protocol or the long GnRH-agonist protocol

The intrafollicular levels of IGF-I and epidermal growth factor (EGF) were studied in women undergoing controlled ovarian hyperstimulation using the multidose GnRH-antagonist protocol or the long agonist protocol, in an attempt to elucidate whether GnRH-antagonists affect the levels of the two growth factors. The follicular fluid concentration of IGF-I, EGF, estradiol and progesterone were detected in 68 women undergoing ovarian hyperstimulation for intracytoplasmic sperm injection (ICSI) cycles. There were no differences in intrafollicular concentrations of EGF and IGF-I in the two studied groups. Additionally, we found no correlation between the intrafollicular levels of IGF-I or EGF and the ICSI outcome. The intrafollicular levels of IGF-I were positively correlated with those of progesterone. In conclusion, the intrafollicular levels of IGF-I and EGF do not seem to be influenced by the stimulation protocol. The intrafollicular levels of both growth factors can not serve as prognostic markers for the ICSI outcome.

Human oocyte cryopreservation: past, present and future

Despite inferior results in the past compared with embryo freezing, oocyte cryopreservation has made great strides in recent years. In fact, it has become a necessity in assisted reproduction technology, providing alternatives to legal, moral and religious problems originating from embryo freezing. Recent advances in freezing technology, modifications of conventional protocols used and continuing optimization of vitrification have efficiently improved the method. A historical description of the method's progression over time, and a comparison of principles, procedures and results as reported in the literature are presented in this review.

Follicular fluid levels of vascular endothelial growth factor and leptin are associated with pregnancy outcome of normal women participating in intracytoplasmic sperm injection cycles

Cytokines play a critical and multifarious role in follicular maturation. Consequently, they may influence the pregnancy outcome in cycles of assisted reproduction. The aim of this study was to measure the levels of tumor necrosis factor-alpha (TNFalpha), vascular endothelial growth factor (VEGF) and leptin in serum and follicular fluids (FFs) from women undergoing controlled ovarian hyperstimulation (COH) for intracytoplasmic sperm injection cycles (ICSI). We tried to investigate their interrelationships and to evaluate them as predictive markers for the cycle's outcome. Seventeen women participated in this study. Male factor infertility was the only indication for ICSI cycles. For COH, the long agonist protocol with triptorelin and recombinant FSH was employed. Cytokines levels were evaluated by ELISA. Serum cytokine levels did not differ between pregnant and non-pregnant women. FF-VEGF levels were significantly elevated in non-pregnant women (722.2+/-1093.2 pg/ml) as compared to pregnant women (290.3+/-259.8 pg/ml). Leptin concentrations were also significantly higher in FFs of non-pregnant women (682.6+/-625.1 ng/ml) than those of pregnant women (231.6+/-286.5 ng/ml). There were significant positive correlations between FF-leptin and age, as well as between FF-leptin and FF-VEGF concentrations. It was concluded that elevated FF-leptin and VEGF levels are associated with failure of conception in IVF cycles and may serve as markers in clinical practice.

Follicular fluid levels of vascular endothelial growth factor and leptin are associated with pregnancy outcome of normal women participating in intracytoplasmic sperm injection cycles

Cytokines play a critical and multifarious role in follicular maturation. Consequently, they may influence the pregnancy outcome in cycles of assisted reproduction. The aim of this study was to measure the levels of tumor necrosis factor-alpha (TNFalpha), vascular endothelial growth factor (VEGF) and leptin in serum and follicular fluids (FFs) from women undergoing controlled ovarian hyperstimulation (COH) for intracytoplasmic sperm injection cycles (ICSI). We tried to investigate their interrelationships and to evaluate them as predictive markers for the cycle's outcome. Seventeen women participated in this study. Male factor infertility was the only indication for ICSI cycles. For COH, the long agonist protocol with triptorelin and recombinant FSH was employed. Cytokines levels were evaluated by ELISA. Serum cytokine levels did not differ between pregnant and non-pregnant women. FF-VEGF levels were significantly elevated in non-pregnant women (722.2+/-1093.2 pg/ml) as compared to pregnant women (290.3+/-259.8 pg/ml). Leptin concentrations were also significantly higher in FFs of non-pregnant women (682.6+/-625.1 ng/ml) than those of pregnant women (231.6+/-286.5 ng/ml). There were significant positive correlations between FF-leptin and age, as well as between FF-leptin and FF-VEGF concentrations. It was concluded that elevated FF-leptin and VEGF levels are associated with failure of conception in IVF cycles and may serve as markers in clinical practice.

The use of cryopreserved mature and immature spermatozoa in assisted reproduction

Treatment of severe male subfertility has become available since the intracytoplasmic injection of a single sperm into an oocyte was successfully applied for the first time in 1992. Moreover, with the use of fresh and cryopreserved epididymal and testicular spermatozoa for this procedure, fertilization and pregnancies could be accomplished. This review addresses the development and performance of these techniques and discusses achievements and problems as well as future aspects of the feasibility of early spermatid injection. Furthermore, limitations of these procedures and concerns with regard to genetic and epigenetic risks of using immature gametes are discussed.

Triptorelin versus cetrorelix in intracytoplasmic sperm injection cycles in women with a single ovary

OBJECTIVE

To compare the response to ovarian stimulation with either the long protocol of a GnRH-agonist or the multiple protocol of a GnRH-antagonist, in women with a single ovary who underwent intracytoplasmic sperm injection (ICSI) cycles.

STUDY DESIGN

Retrospective study including 75 ICSI cycles from 26 women. Sixty-three cycles were stimulated with triptorelin/hMG or rFSH, whereas 12 cycles were stimulated with cetrorelix/hMG or rFSH.

RESULTS

There was not found any statistical significant difference between the two groups regarding the days of stimulation, the number of gonadotropins' ampoules, the peak estradiol levels, the number of aspirated follicles and the number of retrieved oocytes. The fertilization rate, the number of transferred embryos as well as the cumulative embryo score were also similar in both groups.

CONCLUSION

The multiple stimulation protocol of cetrorelix is equally effective with the long protocol of triptorelin in the ovarian stimulation of women with a single ovary.

Gonadotropin releasing hormone antagonists and cryopreservation outcome: a review

REVIEW

The outcome of freeze-thaw cycles with pronuclear stage oocytes or embryos, derived from collecting cycles stimulated with gonadotropin-releasing hormone (GnRH)-antagonists' protocols, was reviewed.

CONCLUSION

The viability of cryopreserved pronuclear stage oocytes and embryos, the quality of transferred embryos and the pregnancy rates of the freeze-thaw cycles seem to be satisfactory regardless of the type and dose of GnRH-antagonist.

[Cumulus cell apoptosis as a predictor for oocyte quality in artificial reproduction technique]

OBJECTIVE

To be able to predict the success of ART reliable tests for determining the quality of the oocytes are necessary. Apart from a vague morphologic assessment via microscopy a direct analysis of the oocyte quality is not possible. Because of the very close relation between the oocyte and the cumulus cells the analysis of the cumulus cells might give sufficient information on the oocyte quality. In this study we correlate the apoptotic activity of cumulus cells to the outcome of fertilized oocytes after Intracytoplasmic Sperm Injection (ICSI).

MATERIAL AND METHODS

246 cumulus-oocyte-complexes from patients undergoing infertility treatment with the ICSI procedure were individually collected. The comet assay was used to determine the proportion of apoptotic cells within the cumulus population of each oocyte and correlated with oocyte fertilization and oocyte quality as well as with pregnancy outcome in 86 patients.

RESULTS

We were able to show that high quality embryos correlate to a low rate of apoptotic cells in their corresponding cumuli. Differences regarding the pregnancy outcome were statistically not significant.

CONCLUSIONS

Our results on cumulus cell apoptosis and embryo quality confirm other publications. To arrive at statistically proven criteria for the further development of single oocytes an increase in the number of analyzed patients is necessary.

A borderline form of empty follicle syndrome. Case report

BACKGROUND

Empty follicle syndrome is known as the failure of oocyte retrieval despite the adequate response to ovarian stimulation. It is a rare phenomenon in in-vitro fertilization and borderline forms of this syndrome have also been described.

MATERIALS AND METHODS

Two cycles in the same patient were stimulated with GnRH agonist/hMG and recFSH; the first followed the long and the second followed the short protocol.

RESULTS

There was a sudden drop in estradiol levels while the ovaries contained a large number of small and medium sized follicles. hCG was administered and oocyte retrieval was performed 36 hours later. There was no indication of low hCG levels. For the first cycle two oocytes were collected: one degenerated and one of poor quality. The second cycle resulted in total failure of oocyte retrieval.

CONCLUSION

The two cycles were classified as borderline forms of empty follicle syndrome. The possible aetiology is discussed.

A comparison of the ovarian response to external stimulation between women with right or left ovary participating in programs of ICSI/ET

INTRODUCTION

Single ovary women compose a group of special interest in assisted reproduction technologies. The aim of the present study was to investigate whether the response to external stimulation and the outcome in women with a single ovary was affected by the location of the ovary.

METHODS

Sixty cycles from 24 women, which stimulated with either hMG or rFSH and a GnRH agonist, were retrospectively studied. Twelve women had right and 12 had left ovary. In all cases, the fertilization was performed by intracytoplasmic sperm injection.

RESULTS

There was not found any statistical significant difference between the two groups regarding the days of stimulation, the peak estradiol levels, the number of aspirated follicles, the number of retrieved oocytes, the fertilization rate and the number of transferred embryos. The cumulative embryo score (CES) was also similar in both groups. Six pregnancies in the group of the right ovary and seven in the group of left ovary were achieved.

CONCLUSION

According to these results, right and left ovary, in single ovary women under external stimulation, are equally active and potent for reproduction.

Increased frequency of X-bearing sperm in males from an infertility clinic: analysis by two-color fluorescence in situ hybridization

Semen samples from 34 men visiting the Lübeck infertility clinic were investigated using a two-color FISH method to determine the ratio of X- and Y-bearing sperm. The overall ratio was significantly shifted to a preponderance of X-containing sperm. A statistical comparison with seven reports from the literature which included 53 normal probands demonstrated in our patients a significant tendency of a preponderance of X-bearing sperm and significantly less Y-bearing sperm. Furthermore, the Lübeck sperm samples are remarkably more heterogeneous in respect to their variability of X- and Y-bearing spermatozoa than in the other mentioned studies with normal probands. These phenomena have to be evaluated in further studies on groups of infertile males showing similar infertility histories.

Comparison of poor responders with good responders using intentionally frozen-thawed epididymal spermatozoa in subsequent ICSI cycles

PURPOSE

To compare the outcome of intracytoplasmic sperm injection (ICSI) cycles performed with frozen-thawed epididymal spermatozoa between patients who respond poorly and patients who respond well to ovarian stimulation.

METHODS

17 patients suffering from obstructive azoospermia underwent microsurgical retrieval of epididymal spermatozoa (MESA) and the spermatozoa were frozen. The frozen-thawed spermatozoa were used in subsequent ICSI cycles. In six patients, the female partners responded poorly to ovarian stimulation. They accomplished nine ICSI cycles. In 11 patients, the female partners responded well to ovarian stimulation and they accomplished 16 cycles.

RESULTS

Poor responders were older than those who reponded well. The mean number of metaphase II oocytes collected was lower in the poor responder group. In the poor responders, two couples failed to fertilise the oocytes in two ICSI cycles. In the good responders, one couple failed to fertilise the oocytes in an ICSI cycle. There were no significant differences in fertilization rates between the two groups. The estradiol concentrations on the day of hCG administration were significantly higher in the good responders. There was no pregnancy in the poor responder group, while three patients who responded well conceived. Eight good responders had 34 supernumerary 2PN oocytes which were cryopreserved.

CONCLUSION

Frozen-thawed epididymal spermatozoa from men with obstructive azoospermia are potent to achieve satisfactory fertilization rates. Poor ovarian response to stimulation induction appears to be the main limiting factor in reaching the stage of embryo transfer. It is preferable in older women to cancel cycles with poor response in the hope that a better response might be obtained in a subsequent cycle. Thus, the frozen-thawed epididymal sperm can be preserved and the most stressful and expensive phase of IVF-ICSI treatment can be avoided.

Outcome of anticipated ICSI cycles using intentionally frozen-thawed testicular spermatozoa according to the spouse's response to ovarian stimulation

PURPOSE

To investigate the outcome of ICSI cycles, using frozen-thawed testicular spermatozoa from patients suffering from non-obstructive azoospermia, in relation to the spouse's response to ovarian stimulation.

METHODS

A retrospective study with two groups of couples where males suffered from non-obstructive azoospermia. In group 1 (n = 14), the female partners responded poorly to ovarian stimulation (< or = 4 oocytes retrieved). In group 2 (n=14), the female partners responded well (> or = 10 oocytes retrieved). Both groups underwent 14 cycles of ICSI using frozen-thawed spermatozoa obtained by TESE.

RESULTS

The total amount of gonadotropin, the duration of stimulation, the peak estradiol concentrations and the number of oocytes were significantly different between the two groups. Despite the satisfactory fertilisation rates, the outcome in poor responders was disappointing due to a low number of oocytes. There was only one pregnancy in the poor responder group whereas there were four in the group that responded well. The pregnancy rates per oocyte collection were 7.14% in group 1 versus 28.57% in group 2. The implantation rates were 60.60% versus 55.33%, respectively.

CONCLUSION

It is possible to achieve satisfactory fertilisation rates using frozen-thawed, surgically-retrieved testicular spermatozoa, but the poor ovarian response to stimulation induction is the limiting factor in reaching implantation and pregnancy. It is preferable that poorly stimulated cycles be canceled, in the hope of a better subsequent response.

Counselling on cryopreservation of pronucleated oocytes

The German Embryo Protection Law permits only the cryopreservation of supernumerary pronuclear stage eggs. Data are needed to counsel patients about their individual benefits from this procedure. All fresh embryo transfer cycles performed from January 1994 until December 1998 in which supernumerary pronucleate eggs were cryopreserved (n = 557) were analysed retrospectively, together with data from all subsequent cycles involving transfers of frozen-thawed pronucleate eggs (n = 420) from January 1994 until June 2001. The additional cumulative pregnancy rate per fresh cycle was 11.5%. This rate depended on the number of embryos per transfer, i.e. 1.9, 8.2 and 13.0% respectively when one, two or three embryos were transferred (P < 0.05). A strong correlation was found between the numbers of cryopreserved pronucleate eggs and pregnancy rates, of 9.3, 10.5 and 17.1% when 1-3, 4-6, or at least 7 pronucleate eggs were available respectively. Additional benefit in terms of this rate from cryopreservation for a patient with and without a pregnancy in the fresh embryo transfer cycles was 5.3 and 12.7% respectively. It is concluded that higher pregnancy rates in cycles involving cryopreserved eggs for patients who did not become pregnant in fresh transfer cycles reveals the disadvantage of the German Embryo Protection Law, which does not allow embryo selection. Therefore, cryopreservation of pronucleate eggs with a higher developmental potential is possible. The total pregnancy rate could be raised from 28.0 to 35.5% per fresh transfer cycle.

Preparation of cycles for cryopreservation transfers using estradiol patches and Crinone 8% vaginal gel is effective and does not need any monitoring

Supernumary pronucleated stage oocytes (PN) can be cryopreserved and later transferred in spontaneous, stimulated or artificial cycles. In this study, we re-evaluated 342 artificial cycles with a transdermal estradiol release system (Estraderm TTS 100) in combination with a vaginal progesterone delivery system (Crinone 8%). Endometrial thickness and serum estradiol on day 14 were correlated with clinical and ongoing pregnancy rates. Endometrial thickness between 7 and 15 mm did not relate to significantly different pregnancy rates. The estradiol serum level did not predict success. In conclusion, this method of endometrial preparation is comfortable for patients and monitoring is unnecessary.