Significant Difference In Fertilization Rates Research Articles

Optimization of conditions for the cryopreservation of Eurasian perch (Perca fluviatilis Linnaeus, 1758) sperm

In this study, a methodical optimization and development of cryopreservation of Eurasian perch (Perca fluviatilis) sperm was carried out. The effects of two extenders (modified Tanaka and Lahnsteiner's immobilizing solution, N = 7 males), 6 dilution ratios (from 1 : 1 to 1 : 50, N = 10 males) and post-thaw storage time (0–6 h, N = 10 males) on post-thaw progressive motility of sperm measured in a CASA system (Computer-assisted Sperm Analysis) were investigated in a wild caught Eurasian perch broodstock collected in the Saska river near Szczytno, Poland. Perch sperm cryopreserved with the modified Tanaka extender showed significantly higher progressive motility after thawing than with the modified Lahnsteiner immobilizing solution. The dilution ratio of 1 : 20 showed higher post-thaw progressive motility than the dilution ratio of 1 : 6 described previously. Post-thaw sperm was sensitive to storage time however the reduction of progressive motility was statistically significant only after 2 h. Thawed sperm resulted in a high fertilization rate (75 ± 5%, N = 9 males) compared to that with fresh sperm (86 ± 5%, N = 9 males). Although the fertilizing capacity has been reduced as a result of cryopreservation, progressive motility did not show a significant reduction in the same experiment (76 ± 24% in fresh sperm and 58 ± 24% in cryopreserved sperm, N = 9 males each). The significant difference in fertilization rates can be attributed to lower individual variation in fertilizing capacity of sperm in comparison to motility.

Clinical results comparison of fresh and vitrified oocytes by intracytoplasmic sperm injection with testicular sperm (TESE-ICSI)

We evaluated the clinical efficacy of vitrified oocytes and fresh testicular sperm in TESE-ICSI for azoospermic patients. Retrospective study. The subjects were 284 couples with 323 oocyte-retrieval cycles for TESE-ICSI at Kyono ART Clinic from January, 1996 to December, 2013. These were divided into 2 groups: group I (vitrified oocytes + fresh testicular sperm) in 73 cycles and group II (fresh oocytes + fresh testicular sperm) in 250 cycles. We assessed the fertilization rate (FR), embryo development, and pregnancy rate (PR) in the two groups including cases of obstructive azoospermia (OA), non-obstructive azoospermia (NOA) and Klinefelter’s syndrome (KS). In group I, the survival rate of oocytes after warming was 88.2% (412/467). There were no significant differences in fertilization rate (57.9% vs. 64.9%), good quality embryo rate (37.9% vs. 38.6%), blastocyst formation rate (45.3% vs. 53.2%), good quality blastocyst rate (19.5% vs. 20.8%), pregnancy rate (33.3% vs. 42.2%) or miscarriage rate (24.3% vs. 22.4%) between group I and group II under OA, NOA and KS. Many studies have shown more positive results after oocyte vitrification than after slow freezing procedures. In this study, there are no significant differences between fresh and vitrified oocytes with TESE-ICSI. The use of vitrified unfertilized oocytes should be recommended for wide medical treatment.

Doors are closing on early development in corals facing climate change.

Marine invertebrates are particularly vulnerable to climatic anomalies in early life history stages because of the time spent in the water column. Studies have focused on the effect of seawater temperature on fertilization, development, and larval stages in corals; however, none of them show comparative results along an environmental gradient. In this study, we show that temperatures in the range of 15–33°C have strong effects on fertilization rates and embryonic stages of two coral species, Acropora muricata in the subtropical environment and Acropora hyacinthus in subtropical and temperate environments. Deformations after the first cleavage stages were observed at low (15°C) and high (33°C) temperatures. Development was delayed by 6–7 h in the slightly non-optimal temperature of 20°C. We found significant differences in fertilization rates and responses of embryos from different latitudes, with temperate corals being more sensitive to extremely hot temperatures and vice versa. We hypothesize that the coral development is restricted to a narrow temperature range and deviation outside this window could inhibit a species' continuance and ecological success. Thus, it would have significant negative effects on adult populations and communities, playing a role in future of coral reef survival.

Fertilization, Hatching, Survival, and Growth of Third-Generation Colored Pearl Oyster (Pinctada martensii) Stocks

In April of 2009, third-generation black (BS3), red (RS3), yellow (YS3), and white (WS3) colored stocks of pearl oyster Pinctada martensii were compared in terms of fertilization, hatching, survival, and growth. Among stocks, there were no significant differences in fertilization rate (P > 0.05; values ranging from 94.8%–98.9%). Hatching rates of WS3 were significantly lower (P < 0.05) at 61.3 ± 6.1% than other stocks (74.3 ± 5.4%, 75.9 ± 5.2%, 73.9 ± 4.9%, for BS3, RS3, and YS3, respectively). Larval survival rates of the BS3 stock (65.8 ± 9.4%), RS3 (61.5 ± 8.7%), and YS3 (58.2 ± 9.2 %) were significantly (P < 0.05) higher than that of the WS3 stock (44.8 ± 11.2%). On day 8, there were no significant differences in mean shell length among the four colored stocks (P > 0.05). At days 15, 23, 90, 150, 210, and 325, however, significant differences in mean shell length among the four colored stocks were observed (P < 0.05). The BS3 stock had consistently larger mean shell length than the other colored stocks.

Intracytoplasmic sperm injection outcome of ejaculated versus extracted testicular spermatozoa in cryptozoospermic men

To compare intracytoplasmic sperm injection (ICSI) outcome of patients with cryptozoospermia after use of ejaculated versus testicular sperm in different cycles of the same patients. Retrospective cohort study. University-affiliated infertility center. A total of 17 patients with cryptozoospermia who underwent a total of 116 ICSI cycles. The patients initially underwent several ICSI cycles using ejaculated sperm (n = 68, 58.6%) that were followed by ICSI cycles using testicular sperm (n = 48, 41.4%). Fertilization rate, pregnancy rate (PR). There were no significant differences in fertilization rates between the two subgroups. A comparison between testicular sperm extraction (TESE) versus ejaculated sperm cycles revealed significantly higher implantation rate (20.7% vs. 5.7%), higher PR (42.5% vs. 15.1%), and higher take home baby rate (27.5% vs. 9.4%). A multivariable logistic regression analysis showed three significant predictors for pregnancy, namely the use of testicular sperm (odds ratio [OR] 5.1, 95% confidence interval [95% CI] 1.8-14.8), use of motile sperm (OR 12.9, 95% CI 2.1-79.1), and female age (OR 0.83, 95% CI 0.7-0.9). Testicular sperm extraction is justified in patients with cryptozoospermia who fail to conceive by ICSI using ejaculated spermatozoa, as it offers higher PR.

Surgically retrieved spermatozoa versus ejaculated spermatozoa in modified natural IVF–ICSI cycles

A retrospective cohort study was performed to evaluate the outcome of modified natural IVF–intracytoplasmic sperm injection (mnIVF–ICSI) cycles to compare 81 mnIVF–ICSI first cycles using ejaculated spermatozoa with 44 mnIVF–ICSI first cycles using surgically retrieved spermatozoa. There were no differences between the two groups in terms of number of oocytes retrieved, oocyte maturity or female age. However, male age was significantly higher in the surgically retrieved compared with the ejaculated group (41.5 versus 36.5years, P=0.001). There were no significant differences in fertilization rate or cleavage rate between the ejaculated and the surgically retrieved groups; however the prevalence of embryo transfer was higher in the surgically retrieved group (65.9% versus 45.7%, P=0.03). Only single-embryo transfer was performed. Biochemical (34.5% versus 37.8%) and clinical (31.0% versus 35.1%) pregnancy rates per embryo transfer were similar between the ejaculated and the surgically retrieved groups. The data suggest that mnIVF–ICSI is an alternative treatment option in couples with severe male factor infertility where surgical sperm retrieval is required.The aim of the present study was to evaluate and compare the outcomes of modified natural IVF–intracytoplasmic sperm injection (mnIVF–ICSI) with surgically retrieved spermatozoa (in male partners with obstructive azoospermia) and ejaculated spermatozoa (in couples with mild-to-moderate male factor). Eighty-one mnIVF–ICSI first cycles using ejaculated spermatozoa were compared with forty-four mnIVF–ICSI first cycles using surgically retrieved spermatozoa. There were no differences between the two groups in terms of number of oocytes retrieved, oocyte maturity or female age. However, male age was significantly higher in the surgically retrieved compared with the ejaculated group. There were no significant differences in fertilization rate, or cleavage rate between the two groups; however, there were more patients having embryo transfers in the surgically retrieved group. Only single-embryo transfer was performed. Biochemical and clinical pregnancy rates per embryo transfer were similar between both groups. The data suggest that mnIVF–ICSI is an alternative treatment option in couples with severe male factor infertility where surgical sperm retrieval is required.

Surrogate in vitro fertilization outcome in typical and atypical forms of Mayer-Rokitansky-Kuster-Hauser syndrome

The genital malformations in Mayer-Rokitansky-Küster-Hauser syndrome (MRKH) are frequently accompanied by associated malformations whose forms were recently classified as typical (isolated uterovaginal aplasia/hypoplasia) and atypical (the addition of malformations in the ovary or renal system). The aim of this study was to compare the surrogate IVF performance of women with typical and atypical forms including their chances of achieving pregnancy. The follow-up data on a total of 102 cycles of surrogate IVF in 27 MRKH patients treated in our department between 2000 and 2010 were analysed. Twenty patients with the typical form who underwent 72 IVF cycles were compared with seven patients with the atypical form who underwent 30 IVF cycles. The various examined parameters of these intended mothers were age, hormonal profile during controlled ovarian hyperstimulation and laboratory outcome. The mean number of gonadotrophin ampoules needed for stimulation and treatment duration was significantly higher in the atypical form (3600 ± 1297IU for 13 ± 2.3 days versus 2975 ± 967 IU for 11.6 ± 1.6 days, P≤ 0.01). Serum estradiol and progesterone levels measured on the hCG administration day were similar. A significantly higher mean number of follicles 12.6 ± 6 versus 8.9 ± 5.4, P≤ 0.03, metaphase II (MII) oocytes 8.7 ± 5.1 versus 6.7 ± 4.8, P≤ 0.05, fertilizations 6 ± 3.6 versus 4.4 ± 3.3, P≤ 0.03 and cleaving embryos 5.7 ± 3.8 versus 4.1 ± 3.3, P≤ 0.01 were available in patients with the typical form compared with those with the atypical form, respectively. There was no significant difference in fertilization rate, cleavage rate or the mean number of transferred embryos. Embryo quality of the transferred ones and pregnancy rate per cycle were also similar between the two groups. Women with the typical form of MRKH needed fewer gonadotrophins and for a shorter duration for ovarian hyperstimulation. The mean number of follicles, oocytes, MII oocytes, fertilizations and cleaving embryos was higher among women with the typical form. Pregnancy rates were similar since the available number and quality of transferred embryos to the surrogate mother were not affected.

Sperm chromatin structure assay results after swim-up are related only to embryo quality but not to fertilization and pregnancy rates following IVF

The aim of this study was to investigate whether the sperm chromatin structure assay (SCSA) results after swim-up are related to fertilization rates, embryo quality and pregnancy rates following in vitro fertilization (IVF). A total of 223 couples undergoing IVF in our hospital from October 2008 to September 2009 were included in this study. Data on the IVF process and sperm chromatin structure assay results were collected. Fertilization rate, embryo quality and IVF success rates of different DNA fragmentation index (DFI) subgroups and high DNA stainability (HDS) subgroups were compared. There were no significant differences in fertilization rate, clinical pregnancy or delivery rates between the DFI and HDS subgroups. However, the group with abnormal DFI had a lower good embryo rate. So, we concluded that the SCSA variables, either DFI or HDS after swim-up preparation, were not valuable in predicting fertilization failure or pregnancy rate, but an abnormal DFI meant a lower good embryo rate following IVF.

Triggering final oocyte maturation with reduced doses of hCG in IVF/ICSI: a prospective, randomized and controlled study

ObjectiveTo compare the effectiveness of urinary human chorionic gonadotropin (u-hCG) at reduced doses of 4000IU and 6000IU in inducing final oocyte maturation during in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles. Study design164 patients with an indication for IVF or ICSI recruited in this randomized, single-blinded and controlled study in IVF clinic at the Sun Yat-sen Memorial Hospital. Patients were prospectively randomized to receive 4000IU (Group A, n=83) and 6000IU (Group B, n=81) of hCG for triggering final oocyte maturation. Number or percentage of mature oocytes retrieved per patient, fertilization rates, pregnancy rates were the main outcome measures. ResultsNo evidence of statistically significant difference in the number or proportion of mature oocytes retrieved was observed in both groups. The lower fertilization rate and significantly lower clinical pregnancy rate were observed in Group A. The ovarian hyperstimulation syndrome (OHSS) rates in both groups were also similar. In the subgroup of BMI<20kg/m2, fertilization rate were significantly higher in the administration group of hCG at the dose of 6000IU when compared with the dose of 4000IU (82.40% vs. 70.92%, P=0.017); in contrast, no significant difference in clinical pregnancy rates was observed in both groups. In the subgroup of BMI 20–25kg/m2, clinical pregnancy rates were significantly higher in patients treated with hCG at dose of 6000IU than patients treated with hCG at dose of 4000IU (65.3% vs. 35.0%, P=0.004); however, no significant difference in fertilization rates was observed. ConclusionBoth doses of u-hCG revealed an equal effect on the induction of final oocyte maturation in the patients with moderate or high ovarian response; however, the reduced dose of hCG could result in an obvious impact on clinical pregnancy rates and did not exhibit an obvious effect on OHSS rates.

Effects of Inbreeding Depression in Pacific AbaloneHaliotis Discus Hannai

To demonstrate inbreeding depression in various traits of Pacific abalone Haliotis discus hannai, 12 inbreeding full-sib families (brother-sister mating) and 13 outbreeding full-sib families were produced by factorial mating using the parents from two full-sib families. All 25 full-sib families were reared for 158 days after settlement, and 8 of the inbred and outbred full-sib families were reared until 3 y 4 mo of age. Inbreeding depression traits between inbred and outbred crosses were compared. No significant differences in fertilization rate, hatchability, and veliger survival rate were observed between the inbreeding and outbreeding crosses. Deformity rate in veliger larvae from the inbred crosses was significantly higher than that among the outbred crosses (t-test, P < 0.01). Significantly lower survival rates were observed in the inbreeding crosses at 109 days after settlement (t-test, P < 0.01) and between 1 y 4 mo-old and 3 y 4 mo-old crosses (t-test, P < 0.05). Mean increases in shell length were not different between the inbred and outbred crosses. Gonad indexes in both crosses were investigated in 3 y 4 mo-old families. The gonad index among inbreeding crosses was significantly lower than that of the outbreeding crosses (analysis of covariance: df = 1, SS = 13.141, F = 25.834, P < 0.01). Significant inbreeding depression in larval deformity rate, juvenile and adult survival rates, and gonad index of Pacific abalone was detected. Although only 2 full-sib families were used as parental broodstock, this is the first long-term rearing examination, from fertilization to adult, of inbreeding depression in Pacific abalone.

Intracytoplasmic sperm injection outcome versus intracytoplasmic morphologically selected sperm injection outcome: a meta-analysis

The development of a modified intracytoplasmic sperm injection (ICSI), called intracytoplasmic morphologically selected sperm injection (IMSI), demonstrated that a profound morphological investigation of the spermatozoon, under the magnification of 6600 x, enables outcome improvement. The aim of this study was to compare ICSI outcome with IMSI outcome. The meta-analysis results demonstrated no significant difference in fertilization rate between ICSI and IMSI groups. However, a significantly improved implantation (odds ratio (OR) 2.72; 95% confidence interval (CI) 1.50-4.95) and pregnancy rate (OR 3.12; 95% CI 1.55-6.26) was observed in IMSI cycles. Moreover, the results showed a significantly decreased miscarriage rate (OR 0.42; 95% CI 0.23-0.78) in IMSI cycles as compared with ICSI cycles. This is the first meta-analysis of published data to evaluate the potential benefits of IMSI. The pooled data of IMSI cycles demonstrate a statistically significant improvement in implantation and pregnancy rates and a statistically significant reduction in miscarriage rates. However, more randomized controlled trials are needed to confirm these results.

A new real-time morphology classification for human spermatozoa: a link for fertilization and improved embryo quality

To understand the correlation between normalcy of the sperm, fertilization, and early embryo development, and to establish a detailed classification scoring scale for the individual spermatozoon with the highest predictive fertilizing potential in real time during intracytoplasmic sperm injection (ICSI). A retrospective and analysis. Laboratory Drouot. 27 couples with male factor infertility referred for ICSI treatment. Before ICSI, motile spermatozoa were scored after aspiration. Oocyte fertilization, embryo development and morphology, outcome of scored motile injected spermatozoa. Our suggested formula is (Normal head score = 2) + (Lack of vacuole score = 3) + (Normal base score = 1) = (Total score = 6) for a morphologic "normal top" spermatozoon, calculated with the major criteria affecting the outcome of ICSI. We take into account the normalcy of head size and shape, the base of the head, and the lack of vacuoles. Our scoring of three classes of injected spermatozoa revealed a statistically significant difference in fertilization rate: 39 out of 46 (84%), 94 out of 128 (73%), and 27 out of 44 (61%), respectively. Our examination of the contribution of maternal age in correlation to sperm score revealed a distinction between oocytes originating from women younger than 30 years and oocytes from women aged 30 years and older. Our suggested classification provides allows the best spermatozoon to be chosen for ICSI, particularly for oocytes from women aged 30 years and older.

Early oocyte penetration can predict the efficiency of bovine embryo production in vitro

The aim of this work was to characterize oocyte fertilization and embryo cleavage in nine AI bulls to find parameters suitable for prediction of in vitro fertility. According to the d8 blastocysts rate, they were categorized as high, medium and low productive (HP, MP and LP, mean: 25.4, 21.0 and 13.6% respectively) bulls. For these categories, oocyte penetration and fertilization efficiency were assessed at 6 and 18 hours post insemination (hpi), respectively. Some presumptive zygotes were cultured and cleaved and fast-cleaved embryo rates were checked at 44 hpi. The penetration rate was significantly higher for HP bulls than for MP and LP bulls (67.9 versus 50.3 and 33.1%; p<0.01). The syngamy rate was significantly higher for HP bulls than for MP and LP bulls (21.4 versus 10.2 and 5.7%; p<0.05). Conversely, no significant differences in fertilization rates were found among HP, MP and LP bulls. The cleavage rate was significantly higher for HP than LP bulls (82.4 versus 74.4%; p<0.01). The fast cleavage rate was significantly higher for both HP and MP bulls, as compared with LP bulls (82.1 and 84.7 versus 73.5%; p<0.01). A strong correlation was found between blastocyst production and penetration (r=0.803), syngamy (r=0.826), cleavage (r=0.635) and fast cleavage (r=0.709). In conclusion, all the evaluated parameters showed a predictive value, the most significant being early penetration and syngamy.

Fresh motile testicular sperm retrieved from nonobstructive azoospermic patients has the same potential to achieve fertilization and pregnancy via ICSI as sperm retrieved from obstructive azoospermic patients

To compare the fertilization and pregnancy rates using fresh testicular sperm between nonobstructive azoospermic (NOA) patients and obstructive azoospermic (OA) patients. We evaluated sperm quality of testicular sperm retrieved by microdissection testicular sperm extraction (MD-TESE) in NOA patients and compared the fertilization rate and pregnancy rate via intracytoplasmic sperm injection (ICSI) between NOA and OA patients. Private hospital-based infertility research laboratory. A total of 58 couples in which the husband was diagnosed with azoospermia. Analytic examination of the outcomes and description of the NOA cases achieving pregnancies; oocyte retrieval and testicular sperm retrieval were performed simultaneously. Comparison of fertilization rate and pregnancy rate at the first ICSI attempt. Testicular sperm were retrieved from 17 of 40 NOA patients and 18 of 18 OA patients. Motile sperm were successfully retrieved from 16 of the 17 NOA patients. There was no significant difference in fertilization rate and pregnancy rate between OA and NOA cases. Of the 17 NOA patients, nine pregnancies were achieved using fresh motile testicular sperm. Fresh motile testicular sperm retrieved from NOA patients may have the same potential to achieve fertilization and pregnancy as sperm retrieved from OA patients. The MD-TESE technique might contribute to the high retrieval rate of fresh motile testicular sperm even in NOA patients.

Inbreeding depression traits in Pacific abalone Haliotis discus hannai by factorial mating experiments

‘Inbreeding depression’ may be an avoidable phenomenon for abalone culture. However, only a few studies have been carried out on inbreeding depression. In the present study, using six families produced in 1994, a factorial mating system including inbreeding and outbreeding was constructed in order to demonstrate inbreeding depression traits of the Pacific abalone. In total, 24 inbreeding and 21 outbreeding crosses were produced during three years (1999–2001) and these off-spring were reared for approximately one year. Significant differences in fertilization rate and growth were not observed between inbreeding and outbreeding corsses. However, the deformity rate of veliger larvae was always higher in inbreeding crosses than that of outbreeding crosses in all experiments. Moreover, a significantly high deformity rate was observed in some full-sib families of inbreeding. Alternatively, the survival rates of inbreeding crosses were much lower than for outbreeding crosses after about 4 months and one year in two rearing localities. These results indicate that inbreeding depression is observed in the traits of deformity rate and survival, but not in fertilization rate nor growth in the first generation of a full-sib family of the Pacific abalone.

Associação entre morfologia do ovócito e taxa de fertilização após ICSI

PURPOSE: to verify the possibility of identifying oocytes that would result in a higher fertilization rate. METHODS: retrospective analysis of the fertilization rate after ICSI of 957 oocytes in metaphase II according to three morphology parameters: cytoplasm inclusions, thickness of the perivitelline space, and fragmentation of the first polar body. Oocytes were obtained from 115 cycles performed among 107 women attended at the Centro de Reproducao Humana de Campinas, from April to December of 2004. For the statistical analysis of differences in the fertilization rate between 'normal' oocytes and those presenting each alteration, the c2 test was used with confidence levels of 5 and 10%. RESULTS: no significant difference in fertilization rate was observed regarding characteristics of the polar body or thickness of the perivitelline space. Fertilization rate among oocytes with perivitelline space with debris was 14 percentage points lower than among oocytes with absent space (p=0.055) and the rate among oocytes with granular cytoplasm was seven percentage points lower than among oocytes with normal cytoplasm (p 0.05). CONCLUSIONS: the morphological parameters of oocytes currently being evaluated do not allow us to clearly distinguish those that would lead to a higher fertilization rate and could be used in clinical practice.

Choosing fertilization method by analyzing sperm morphology or by performing swim‐up preparation

Evaluation of sperm morphology has been used as a screening method for choosing between intracytoplasmic sperm injection (ICSI) and conventional in vitro fertilization (IVF). However, sperm morphology analysis is a time-consuming and often subjective scoring method, and may lead to an unnecessarily large proportion of invasive and costly ICSI treatments. The aim of this study was to evaluate if the yield after swim-up preparation could be of advantage over sperm morphology evaluation for choosing fertilization method. In the first part of the study 53 split cycles with less than 5% normal forms in the ejaculate were retrospectively evaluated. Part 2 is a prospective evaluation including 357 cycles where the number of sperm available after a standardized swim-up procedure was used for choosing fertilization method. In all cycles where < or = 1 million sperm were obtained after swim-up, conventional IVF was performed. In the first part no statistically significant difference in fertilization rates was found for IVF and ICSI respectively (59.2% versus 64.7%). Four IVF cycles ended up in total fertilization failure (TFF) while in no ICSI cycle was TFF obtained. In the second part 8.9% TFF was obtained in the poor sperm morphology group compared to 1.3% in the good morphology group. These TFF corresponded to 1% of all our treatment cycles. The present strategy reduced ICSI treatments by 10%, thereby reducing the cost and workload. It can be discussed if an increase of TFF in absolute number of eight is balanced by a reduced workload of 100 ICSI treatments.

A prospective randomized trial of conventional in vitro fertilization versus intracytoplasmic sperm injection in unexplained infertility

To compare outcomes in patients with unexplained infertility undergoing conventional in vitro fertilization (IVF) versus intracytoplasmic sperm injection (ICSI). Sixty women with unexplained infertility in a Canadian tertiary-level clinic were randomized to IVF or ICSI. Subjects underwent downregulation with gonadotropin-releasing hormone agonist prior to initiation of recombinant human follicle-stimulating hormone. The primary outcome measure was fertilization rate. Secondary outcomes included implantation rate, embryo quality, clinical pregnancy rate, and live birth rate. There was no statistically significant difference in fertilization rate (77.2% IVF vs. 82.4% ICSI), implantation rate (38.2% IVF vs. 44.4% ICSI), clinical pregnancy rate (50% in each group), or live birth rate (46.7% IVF vs. 50% ICSI). There were two cases of failed fertilization in the IVF group. There was no significant difference in embryo quality between groups. There were no differences in clinical outcomes associated with IVF versus ICSI in the treatment of unexplained infertility.

Impact of follicular-fluid meiosis-activating sterol in an albumin-based formulation on the incidence of human pre-embryos with chromosome abnormalities

To evaluate the effect of adding follicular-fluid meiosis-activating sterol (FF-MAS) in a novel 0.2% recombinant human albumin-based formulation to cumulus-enclosed oocytes on chromosomal status and development of pre-embryos. Multicenter, prospective, randomized, open (double-blind for vehicle and FF-MAS groups), four parallel groups, controlled trial. Four public IVF clinics in Denmark. Two hundred eighteen women undergoing IVF donated 483 oocytes. Follicle-stimulating hormone/hCG-primed cumulus-enclosed oocytes randomized to 4 hours of exposure to medium with 1 or 10 micromol/L of FF-MAS dissolved in 0.2% recombinant human albumin, medium with 0.2% recombinant human albumin (vehicle control), or medium alone (control) before insemination. Primary endpoint: incidence of human pre-embryos with chromosomal abnormalities. Secondary endpoint: fertilization rate, cleavage rate, and pre-embryo quality assessed after 68 hours of culture. At pre-embryo level, the overall abnormality rates in the control, vehicle control, and 1- and 10-micromol/L FF-MAS groups were 53%, 39%, 42%, 53%, respectively, and at blastomere level 49%, 44%, 44%, and 48%, respectively. After 20 and 26 hours, the fertilization rates were between 67% and 71% in all groups. No differences in the cleavage rates were observed. The concentrations of FF-MAS in a novel 0.2% recombinant human albumin-based formulation of FF-MAS did not increase the risk of chromosomal abnormalities in pre-embryos or blastomeres. No statistically significant differences in fertilization rate, cleavage rate, or number of good quality pre-embryos were found among the four groups.

The successful double cryopreservation of rabbit ( Oryctolagus cuniculus) semen in large volume using the directional freezing technique with reduced concentration of cryoprotectant

Using directional freezing, our objective was to cryopreserve rabbit semen and achieve fertility that was equal or higher than that achieved with conventional freezing. The working hypothesis was that controlling the ice-front propagation would allow reduction of DMSO concentration to <1 M, in addition to the capability to freeze large volumes (2–10 mL). Moreover, single and double freezing of semen were used to demonstrate the abbreviated mechanical stress imparted by directional freezing. Single-cryopreserved semen from 15 males extended with 0% egg yolk/1.75 M DMSO, 15.3% egg yolk/0.88 M DMSO and 20% egg yolk/0 M DMSO resulted in lower ( P < 0.05) mean ± S.E.M. post-thaw motility (3.6 ± 1.1, 28.5 ± 2.8 and 36.3 ± 1.8%, respectively) compared to fresh semen (73.3 ± 1.2%). Semen from seven of these males, subject to double freezing using only egg yolk based extenders, resulted in post-thaw motilities of 18.1 ± 2.2 and 16.4 ± 3.3%. Despite the reduced functional parameters of cryopreserved semen, fertility and kindling rates of 73.9 and 56.5% for single frozen-thawed, and 28.6 and 35.7% for double frozen-thawed semen were achieved (with insemination of 98 females). There was no significant difference in fertility rate between fresh semen (87.5%) and semen that was single frozen-thawed with the 15.3% egg yolk/0.88 M DMSO extender (73.9%). In conclusion, cryopreservation of rabbit semen in large volumes using directional freezing achieved fertility rates similar to those achieved with fresh semen. Furthermore, acceptable fertility rates with double frozen-thawed semen could facilitate the future use of sex-sorted semen in rabbits.