Embryos from vitrified vs. fresh oocytes in an oocyte donation program: a comparative morphokinetic analysis.

OBJECTIVE: To compare the morphokinetic patterns of human embryos originating from vitrified oocytes (VITRI group) with those derived from freshly collected oocytes (CONTROL group) in oocyte donation cycles. DESIGN: This is a retrospective observational study. SETTING: Embryolab Fertility Clinic, Embryology Lab, Thessaloniki, Greece. PATIENT(S): The study included embryos from 421 vitrified oocytes from 58 oocyte donation cycles and 196 fresh oocytes from 23 oocyte donation cycles. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Key time parameters, dynamic events, fertilization rates, degeneration rates, cleavage rates, blastocyst rates, pregnancy rates, clinical pregnancy rates, implantation rates, and live birth rates were estimated. RESULTS: The mean survival rate of vitrified oocytes was 92.58% (±7.42%). Fertilization rates were significantly different between the 2 groups (VITRI group: 71.92% ± 20.29% and CONTROL group: 80.65% ± 15.22%) whereas the degeneration, cleavage, blastocyst, pregnancy, clinical pregnancy, ongoing pregnancy, implantation, and live birth rates were not significantly different between embryos derived from fresh or vitrified oocytes. Time-lapse analysis showed no significant difference in any key time parameter. However, when examining dynamic parameters, first cell cycle (CC1) (t2 - tPB2: from the second polar body extrusion (tPB2) up to 2 cells (t2)) showed a significant difference whereas CC1a (t2 - tPNf: from fading of the pronuclei (tPNf) up to 2 cells (t2)) was at the threshold of significance. CONCLUSION(S): CC1 in vitrified oocytes exhibited a comparatively slower progression in contrast to fresh oocytes. Conversely, CC1a in vitrified oocytes demonstrated faster progression compared with fresh oocytes. It is worth noting that these temporary deviations had minimal impact on the subsequent development. Despite the clinical outcomes showing a decrease in the vitrified group, none of them reached statistical significance. This lack of significance could be attributed to the limited sample size of the study.

Double vitrification of embryos adversely affects clinical outcomes.

OBJECTIVE: To evaluate the impact of double embryo vitrification on clinical outcomes. METHODS: This retrospective cohort study included data from January 2013 to March 2021. The study group included women aged 33.3±5.7 years with double-vitrified embryos (n=381), while the control group included women aged 32.1±6.7 years with embryos vitrified once (n=780), all transferred at the blastocyst stage. The primary endpoint was live birth rate (LBR), and secondary endpoints included percent positive ßHCG test, clinical/ongoing pregnancy rates, miscarriage/biochemical pregnancy rates and birthweight. RESULTS: LBR was significantly lower in double-vitrified embryos (30.2%) than in embryos vitrified once (45.6%, p<.05). Similarly, double-vitrified embryos were associated with significantly lower positive ßHCG tests (46% vs. 63.3%, p<.05) and clinical (34.9% vs. 52.2%, p<.05) and ongoing pregnancy (31.3% vs. 47.3%, p<.05) rates compared to embryos vitrified once. However, biochemical pregnancy (double vitrified: 24.1% vs. vitrified once: 17.9%, p>.05) and miscarriage rates (double vitrified: 10.2% vs. vitrified once: 9.4%, p>.05), as well as mean birthweight (double-vitrified embryos: 2950g vs. embryos vitrified once: 2837g, p>.05) did not differ significantly between two groups. On a secondary comparison, amongst double-vitrified embryos, the subgroup that was cultured for more than 24 hours between warming and second vitrification achieved significantly higher positive ßHCG tests (49%) and clinical pregnancy (38%) rates, compared to embryos re-vitrified on the same day of warming (31.8% and 20.5%, respectively, p<.05). Nevertheless, LBR did not differ significantly amongst these study-group embryos (embryos that remained in culture for more than 24 hours: 32.2% vs. embryos that were re-vitrified on warming day: 20.5%, p>.05). CONCLUSIONS: Double vitrification of embryos adversely affects clinical outcomes. However, it represents a valuable option concerning embryo wastage, with acceptable success rates.

The impact of fresh and frozen testicular tissue quality on embryological and clinical outcomes.

Our ability to predict the potential of testicular spermatozoa to support embryonic development is still limited. Although motility of testicular spermatozoa is associated with embryo development, the impact of morphology and the presence of spermatozoa in the testicular sample has not been previously researched. Moreover, while the majority of data indicate no effect of cryopreservation, there are studies reporting impaired clinical outcomes due to testicular cryopreservation. In a retrospective study, 118 ICSI-TESE cycles were analysed to study the impact of (a) total quality of testicular tissue, (b) testicular tissue cryopreservation and (c) presence/motility/morphology of testicular spermatozoa in fertilisation rate, embryonic development, clinical pregnancy (CPR), ongoing pregnancy (OPR) and live birth rate (LBR). Results showed that fertilisation rate was significantly affected by both total quality of testicular tissue (p < .05) and rare presence of spermatozoa (p < .01). Moreover, total tissue quality (p < .01), cryopreservation of low-quality samples (p < .01), absence of motile testicular spermatozoa (p < .01) and poor spermatozoa morphology (p < .05) had a negative impact on the number of good quality day 3 embryos. CPR, OPR or LBR was not affected by any parameters examined. Our data suggest that the quality of testicular tissue influences both fertilisation rate and embryo development. Moreover, cryopreservation of low-quality testicular samples has a negative impact on the number of available embryos for transfer.

Closed vs. Open Oocyte Vitrification Methods Are Equally Effective for Blastocyst Embryo Transfers: Prospective Study from a Sibling Oocyte Donation Program.

PURPOSE: To assess whether open and closed vitrification protocols are equally effective for sibling-oocyte cycles when performing blastocyst embryo transfers. MATERIALS AND METHODS: A prospective study was set up comparing the open and the closed vitrification techniques in oocyte recipients sharing sibling oocytes between 2014 and 2016. Sibling oocytes were randomly and equally assigned into the closed group (oocytes vitrified in a closed system) or the open group (oocytes vitrified in an open system). Intracytoplasmic sperm injection was performed on all cases. Embryo transfers were performed on day 5. Power analysis calculation showed that 94 cycles would be needed for each group in the study in order to achieve statistical significance at a 5% level with power 80%. RESULTS: The final number of donors included was 95. A total of 190 recipients matched with their donors were included in the study. There was no difference in the mean number of oocytes vitrified with the closed or the open system (8.26 ± 2.54 vs. 8.31 ± 2.57). No significant difference was observed between the 2 groups regarding survival rate, fertilization rate, cleavage rate, top-quality embryos on day 3, blastocyst rate, and top-quality blastocyst rate. Moreover, no statistically significant difference in the b-human chorionic gonadotropin-positive rate, clinical pregnancy rate per cycle, implantation rate, ongoing pregnancy rate, and live birth rate between closed and open groups. CONCLUSION: Οpen and closed vitrification protocols are equally effective for sibling-oocyte cycles.

Spindle and chromosome configuration analysis of human biopsied versus non-biopsied embryos by confocal laser scanning microscopy following vitrification.

SummaryThe aim of this study was to investigate the effects of zona drilling and biopsy on day 3 followed by vitrification on day 5 on the cytoskeleton and development of human embryos, by analysing survival rates and spindle and chromosome configurations by fluorescence and confocal laser scanning microscopy in human biopsied and non-biopsied embryos. In total, 98 human blastocysts (50 non-biopsied and 48 following biopsy on day 3) were vitrified on day 5 using either a commercial dimethyl sulphoxide (DMSO)-free vitrification kit or increasing concentrations of DMSO/EG (5%/5-10%/10-20%/20%). Following warming, the blastocysts were allowed to recover in culture for 24 h and were immunostained with α-tubulin, acetylated tubulin, and/or γ-tubulin antibodies in combination with 4',6-diamidino-2-phenylindole (DAPI). Labelled embryos were examined by both fluorescence and confocal laser scanning microscopy. The survival rates following warming (92% non-biopsied vs 83.3% biopsied) and the incidence of normal spindle chromosome configurations was not statistically different between the two groups (65.2% non-biopsied vs 59.2% biopsied, P>0.05). The incidence of spindle abnormalities including multipolarity, chromosome lagging, congression failure and chromosome bridging were also similar between the two groups (P>0.05). This study is the first to compare the incidence of cytoskeletal abnormalities in biopsied and non-biopsied human embryos following vitrification. We conclude that there was no significant difference in the survival rates and the incidence of spindle abnormalities between the two groups.

The impact of sperm DNA fragmentation on ICSI outcome in cases of donated oocytes.

PURPOSE: The aim of this study is to evaluate the sperm DNA fragmentation index (DFI) in oocyte donation cycles and correlate it with the sperm parameters, the male characteristics, the embryo quality and the outcome of intracytoplasmic sperm injection (ICSI). METHODS: A total of 150 couples participating in an oocyte donation program were included in the study. Sperm samples were assessed by conventional sperm analysis. DFI was evaluated using the Halosperm kit, a sperm chromatin dispersion test (SCD). RESULTS: The relations between DNA damage and epidemiological male factors (age, height, weight), standard semen parameters (concentration, total and forward motility, and morphology), and embryological and clinical parameters (fertilization rate, total blastocyst number, number of good quality blastocyst, clinical pregnancy) were analyzed. DFI was positively correlated with advanced male age (r = 0.23, p < 0.05) and negatively correlated with total sperm and forward motility (r = - 0.29, r = - 0.27, respectively; p < 0.05). DFI was not significantly correlated with pregnancy outcome in oocyte donation cycles (r = - 0.05, p > 0.05). When good quality blastocysts were chosen, a trend toward the development of good quality embryos was detected in the presence of a low DFI (r = - 0.20, p = 0.08). CONCLUSIONS: DFI does not significantly affect the outcome of ICSI in oocyte donation cycles. Even in cases of advanced paternal age that a high DFI resulted sperm DNA fragmentation seems not to adversely affect the final outcome.

Declining Sperm Counts or Rather Not? A Mini Review.

IMPORTANCE: Temporal global trends of sperm quality remain a matter of debate. OBJECTIVE: The aim of this study was to present a comprehensive review of studies reporting on sperm quality counts, summarize the main end points, and assess the main reasons for potential discrepancies. EVIDENCE ACQUISITION: An evidence-based review of PubMed and Scopus databases was performed regarding studies reporting on modification of sperm quality counts, independently of study character, study language, or date. RESULTS: Since the meta-analysis of Carlsen et al in 1992 (Br Med J 1992;305:609-613) that suggested an annual decline in sperm count of 1%, several reports confirmed the decline in sperm quality, whereas others disproved them, suggesting a slight increase or absence of change in sperm count. Such controversies may be attributed to geographical and time-related variability in sperm values and also to several confounding factors that influence the semen parameters. Intrinsic weaknesses of the studies include heterogeneity of subjects recruited, lack of adjustment for confounding factors, and samples that do not always represent the general population. CONCLUSIONS: No consensus exists on whether sperm counts actually decrease because studies' results are often controversial or inconclusive with methodological deficiencies. More prospective, large-scale, population based studies are needed in order to provide sound evidence of possible global trends in sperm count.

GnRH antagonist administered twice the day before hCG trigger combined with a step-down protocol may prevent OHSS in IVF/ICSI antagonist cycles at risk for OHSS without affecting the reproductive outcomes: a prospective randomized control trial.

PURPOSE: The purpose this study is to investigate whether a double antagonist dose (0.25 mg/12 h) administered the day before hCG trigger is effective in preventing ovarian hyperstimulation syndrome (OHSS) in GnRH antagonist IVF/intracytoplasmic sperm injection (ICSI) cycles at risk for OHSS. METHODS: This is a prospective randomized control study, conducted from November 2012 to January 2016. A total of 194 patients undergoing a IVF/ICSI GnRH antagonist cycle that were at risk of OHSS and chose to proceed with embryo transfer and avoid cycle cancellation or embryo cryopreservation were allocated into two groups. The inclusion criteria consisted of a rapid rise of oestradiol ≥ 3500 pg/ml combined with ≥ 18 follicles > 11 mm in diameter without any mature follicle > 16 mm, in any day of stimulation. Overall, 97 patients (intervention group A) received a double dose of GnRH antagonist (0.25 mg/12 h) the day before hCG while 97 patients (control group B) did not. Recombinant FSH administration was tapered to 100 IU/24 h the day of the allocation in both groups. RESULTS: Incidence of early-onset moderate/severe OHSS was significantly lower in intervention group A compared to control group B (0 vs 12.37%, P < 0.001). Clinical pregnancy rate per cycle (50.52 vs 42.27%, P = 0.249) was not significantly different between the two groups. Oestradiol (3263.471 ± 1271.53 vs 5233 ± 1425.17, P < 0.001), progesterone (0.93 ± 0.12 vs 1.29 ± 0.14, P < 0.001) and luteinizing hormone (1.42 ± 0.31 vs 1.91 ± 0.33, P < 0.001) were significantly lower in group A the day of the hCG triggering. CONCLUSION: The administration of a rescue double GnRH antagonist dose the day before hCG trigger may represent a safe alternative preventive strategy for early OHSS without affecting the reproductive outcomes. TRIAL REGISTRATION NUMBER: ISRCTN02750360.

How does closed system vitrification of human oocytes affect the clinical outcome? A prospective, observational, cohort, noninferiority trial in an oocyte donation program.

OBJECTIVE: To evaluate whether is possible to vitrify oocytes in an aseptic (hermetically closed) fashion and maintain clinical results comparable with those of fresh oocytes. DESIGN: Prospective, observational, cohort, noninferiority trial. SETTING: Private in vitro fertilization center. PATIENT(S): One hundred eighty-four recipients of donated vitrified oocytes. INTERVENTION(S): Closed system vitrification. MAIN OUTCOME MEASURE(S): Pregnancy rate per cycle and clinical pregnancy rate per cycle. RESULT(S): No statistically significant differences were observed between two groups regarding the pregnancy rate per cycle (63.1% vs. 60.9%) or the clinical pregnancy rate per cycle (55.4% vs. 58.7%). Biochemical pregnancy rate was statistically significantly higher in the fresh group (7.6% vs. 2.2%). The mean number of embryos transferred was similar (2.0 ± 0.0 vs. 1.97 ± 0.3). Concerning embryologic data, there were no statistically significant differences regarding the fertilization, cleavage, top quality day-3 embryo, or blastocyst rates, whereas the top quality blastocyst rate on day 5 was statistically significantly higher in the fresh oocyte group (31.7% vs. 26.1%). CONCLUSION(S): Aseptically (in a closed system) vitrified oocytes show similar clinical efficiency compared with their sibling fresh oocytes.

GnRH antagonist versus long GnRH agonist protocol in poor IVF responders: a randomized clinical trial.

OBJECTIVE: To compare the efficacy of the long GnRH agonist and the fixed GnRH antagonist protocols in IVF poor responders. STUDY DESIGN: This was a randomized controlled trial performed in the Iakentro IVF centre, Thessaloniki, from January 2007 to December 2011, concerning women characterised as poor responders after having 0-4 oocytes retrieved at a previous IVF cycle. They were assigned at random, using sealed envelopes, to either a long GnRH agonist protocol (group I) or a GnRH antagonist protocol (group II). RESULTS: Overall 364 women fulfilled the inclusion criteria and were allocated to the two groups: finally 330 participated in our trial. Of these, 162 were treated with the long GnRH agonist protocol (group I), and 168 with the fixed GnRH antagonist protocol (group II). Numbers of embryos transferred and implantation rates were similar between the two groups (P=NS). The overall cancellation rate was higher in the antagonist group compared to the agonist group, but the difference was not significant (22.15% vs. 15.2%, P=NS). Although clinical pregnancy rates per transfer cycle were not different between the two groups (42.3% vs. 33.1%, P=NS), the clinical pregnancy rate per cycle initiated was significantly higher in the agonist compared to the antagonist group (35.8% vs. 25.6%, P=0.03). CONCLUSIONS: Although long GnRH agonist and fixed GnRH antagonist protocols seem to have comparable pregnancy rates per transfer in poor responders undergoing IVF, the higher cancellation rate observed in the antagonist group suggests the long GnRH agonist protocol as the first choice for ovarian stimulation in these patients.

GnRH antagonists and endometrial receptivity in oocyte recipients: a prospective randomized trial.

The effect that gonadotrophin-releasing hormone (GnRH) antagonists exert on endometrial receptivity has not yet been elucidated. GnRH antagonists might directly affect oocytes, the embryo and/or the endometrium. The aim of this study was to investigate the direct effect of GnRH antagonists on the endometrium in oocyte donation cycles. In an oocyte donation programme, oocytes from each donor (n = 49), stimulated with gonadotrophins and a GnRH antagonist, were equally shared between two different matched recipients. Recipients were randomly allocated to either receive a GnRH antagonist concomitant to donor during their endometrial priming with oestradiol (group I, n = 49) or to solely continue with their endometrial preparation (group II, n = 49). Pregnancy rate was 55.1% in group I and 59.1% in group II. Implantation rate was 26.1% in group I and 24.4% in group II. Endometrial thickness was also similar between the two groups on the day of human chorionic gonadotrophin injection to the donor. In conclusion, GnRH antagonist administration during the proliferative phase at a dose of 0.25 mg per day does not appear to adversely affect endometrial receptivity in oocyte recipients.

Low-dose human chorionic gonadotropin during the proliferative phase may adversely affect endometrial receptivity in oocyte recipients.

The effect of low-dose human chorionic gonadotropin (hCG) administration in the proliferative phase of oocyte recipients was investigated in a prospective randomized trial. Sibling oocytes from the same donor were shared at random among two different recipients. In group I oocyte recipients received 750 IU of hCG every three days concomitant to endometrial preparation with estradiol until hCG injection to the donor, whereas in group II recipients received no hCG during endometrial priming with estradiol. Endometrial thickness was significantly lower in group I compared with group II, although similar endometrial thickness was detected during the mock cycle. Pregnancy rates were significantly lower in group I than in group II (13.6% vs. 45.4%, p<0.05). Implantation rates were also significantly lower in group I (1.7% vs. 22.4%, p<0.01). The study was discontinued prematurely for ethical reasons when 22 cycles were completed, as pregnancy rates were very low in group I. In conclusion, hCG administration in the proliferative phase might directly affect endometrial proliferation and receptivity.