Indirect markers of oocyte quality in patients with ovarian endometriosis undergoing IVF/ICSI: a systematic review and meta-analysis.

This systematic review and meta-analysis aimed to evaluate the impact of ovarian endometriomas (OMA) on indirect markers of oocyte quality in patients undergoing IVF, compared with women without anatomical or functional ovarian abnormalities. The search spanned original randomized controlled trials, case-control studies and cohort studies published in MEDLINE, the Cochrane Controlled Trials Register and the ClinicalTrials.gov database up to October 2023. Thirty-one studies were included in the meta-analysis, showing no significant differences in fertilization (OR 1.10, 95% CI 0.94-1.30), blastulation (OR 0.86, 95% CI 0.64-1.14) and cancellation (OR 1.06, 95% CI 0.78-1.44) rates. However, patients with OMA exhibited significantly lower numbers of total and mature (metaphase II) oocytes retrieved (mean difference -1.59, 95% CI -2.25 to -0.94; mean difference -1.86, 95% CI -2.46 to -1.26, respectively), and lower numbers of top-quality embryos (mean difference -0.49, 95% CI -0.92 to -0.06). The Ovarian Sensitivity Index was similar between the groups (mean difference -1.55, 95% CI -3.27 to 0.18). The lack of data published to date prevented meta-analysis on euploidy rate. In conclusion, although the presence of OMA could decrease the oocyte yield in patients undergoing IVF/intracytoplasmic sperm injection, it does not appear to have an adverse impact on oocyte quality.

Cryopreservation of sperm from the gudgeon, Microphysogobio rapidus (Cyprinidae): Effects of cryoprotectant, diluents, and dilution ratio.

We investigated methods for cryopreserving sperm from the endangered gudgeon, Microphysogobio rapidus, by examining the effects of cryoprotective agent (CPA) concentration, diluent, and dilution ratio on post-thaw sperm quality. The quality of frozen sperm was evaluated in terms of motility and kinematic parameters, viability, DNA damage, and fertilization rate. We evaluated methanol, glycerol, dimethyl sulfoxide (DMSO), and ethylene glycol as CPAs. Sperm motility, velocity, and viability were significantly higher when methanol was used as the CPA (p < 0.05). The diluents tested were Ringer's solution, Kurokura's Extender, Common Carp Sperm Extender (CCSE), and buffered sperm motility-inhibiting saline solution (BSMIS); post-thaw motility was highest when Ringer's solution was used as the diluent. Next, various quantities of methanol were combined with Ringer's solution to identify the optimal dose of methanol. The dilution ratios tested ranged from 1:1 to 1:7. Cryopreserved sperm was thawed at 20 °C for 15 s. The use of 10% methanol with Ringer's solution at a dilution ratio of 1:5 resulted in the highest post-thaw sperm motility, viability, and velocity including VAP, VCL, and VSL. Post-thaw sperm showed significantly greater DNA damage than the control (fresh sperm) (p < 0.05). The fertilization rate was highest with fresh sperm (p < 0.05), followed by sperm frozen with 10% methanol + Ringer's solution. We recommend that the best way to preserve sperm in the studied species is to use a combination of Ringer's solution and 10% methanol at a 1:5 dilution ratio. Our findings will facilitate the artificial fertilization of M. rapidus.

Effect of intravenous anesthetic drugs on fertilization rate in oocyte retrieval.

BACKGROUND: The purpose of this study was to investigate the effects of intravenous anesthetic drugs on fertilization rate in subjects receiving oocyte retrieval by assisted reproduction technology (ART). METHODS: A retrospective cohort study was designed. The clinical information of subjects who received oocyte retrieval procedure was collected. The subjects were divided into two groups based on the type of anesthesia used: the no-anesthesia group and the intravenous anesthesia group. Propensity score matching (PSM) was performed and multiple linear regression analyses were conducted. Fertilization rate was compared between the two groups before and after PSM. RESULTS: A total of 765 subjects were divided into two groups: the no-anesthesia group (n = 482) and the intravenous anesthesia group (n = 283). According to propensity scores, 258 pairs of subjects were well matched, and the baseline data between the two groups were not significantly different (P > 0.05). Fertilization rate was 77% in the intravenous anesthesia group, and 76% in the no-anesthesia group, without significant between-group difference (P = 0.685). Before matching, Poisson regression analysis showed no effect of intravenous anesthetic drugs on fertilization rate (RR = 0.859, 95%CI: 0.59 to 1.25, P = 0.422). After matching, no difference was found either (RR = 0.935, 95%CI: 0.67 to 1.29, P = 0.618). CONCLUSION: Intravenous anesthetic drugs may exert no effects on fertilization rate in subjects receiving ART.

Hashimoto's Thyroiditis Negatively Influences Intracytoplasmic Sperm Injection Outcome in Euthyroid Women on T4 Substitution Therapy: A Retrospective Study.

OBJECTIVE: The objective of this study was to analyze the impact of thyroid autoimmunity (TAI) on reproductive outcome parameters of intracytoplasmic sperm injection (ICSI) cycles as compared to TAI-negative ICSI cycles. DESIGN: In this single in vitro fertilization (IVF) center retrospective study, 86 infertile women with elevated thyroid peroxidase or TGAb levels, but euthyroid after thyroxine replacement (study group), were compared to 69 female patients with no thyroid abnormalities (controls). Following ICSI treatment fertilization rate (FR), clinical pregnancy rate (CPR), miscarriage rate (MR), and live birth rate (LBR) were analyzed. MATERIALS, SETTING, METHODS: All subjects with various infertility factors were treated with ICSI in university-based IVF center. Patients in the study group received thyroxine replacement and were euthyroid at IVF treatment. Before the IVF cycles, endocrinological parameters were uniformly assessed: thyroid function and antibodies, reproductive hormones (anti-Müllerian hormone [AMH], follicular stimulating hormone [FSH], luteinizing hormone, E2, PRL, testosterone, DHEAS, 17-OHP, AD) and OGTT (0-60-120 min glucose and insulin). Following descriptive comparison of laboratory parameters, age-adjusted analyses of FR, CPR, MR, and LBR were performed. RESULTS: TAI-positive women were older (mean age 35.31 ± 4.95 vs. 32.15 ± 4.87 years; p = 0.002), had higher FSH (8.4 ± 3.4 vs. 7.4 ± 2.32 U/L; p = 0.024), higher E2 (53.94 ± 47.61 vs. 42.93 ± 18.92 pg/mL; p = 0.025) levels, while AMH (2.88 ± 2.62 vs. 3.61 ± 1.69 ng/mL; p = 0.0002) was lower. There were no differences in TSH levels (1.64 ± 0.96 vs. 1.66 ± 0.65 µIU/mL; p = 0.652) between the two groups. FT3 (2.63 ± 0.58 vs. 2.98 ± 0.55 pg/mL; p = 0.002) was lower and FT4 (1.3 ± 0.29 vs. 1.13 ± 0.21 ng/dL; p = 0.0002) was higher in the TAI-positive group, reflecting clinically irrelevant differences. Egg cell counts (6 ± 3.8 vs. 7.5 ± 3.95; p = 0.015) were lower in TAI and remained so following age adjustment. Although the overall ICSI FR did not differ (62.9% vs. 69.1%, p = 0.12), it was lower for patients under 35 with TAI showing decreasing differences in line with age. The CPR (36.04% vs. 69.56%; p < 0.001) and LBR (23.25% vs. 60.86%; p < 0.001) were lower, the MR (35.48% vs. 12.5%; p = 0.024) was higher in the TAI group, and these differences remained after age adjustment. LIMITATIONS: Since the higher age of the study group may interfere with the effect of TAI, age adjustment calculations were necessary to perform to eliminate this confounding factor. CONCLUSION: Despite optimal thyroid supplementation in clinical or subclinical hypothyroidism, the presence of TAI negatively influences CPR and is connected to a higher MR, thus resulting in a lower LBR after ICSI. Decreased FR with ICSI in TAI patients may also contribute to poorer outcomes, especially in younger women.

Ambient air pollution decreased normal fertilization rate via the mediation of seminal prosaposin.

OBJECTIVE: This study focuses on the association between seminal concentration of prosaposin and ambient air pollutants and whether the association affects the normal fertilization rate in vitro fertilization (IVF) treatment. METHODS: The cohort of 323 couple participants aged 22-46 was recruited from Jan. 2013 to Jun. 2018. At enrollment, resident address information was obtained and semen parameters of male counterparts were evaluated according to WHO criteria. We used inverse distance weighting interpolation to estimate the levels of ambient pollutants (SO2, O3, CO, NO2, PM2.5, and PM10) in the surrounding area. The exposure of each participant was estimated based on the data gathered from air quality monitoring stations and their home address over various periods (0-9, 10-14, and 0-90 days) before semen sampling. The generalized linear regression model (GLM) and the Bayesian kernel machine regression (BKMR) were used to analyze the associations between pollutants, semen parameters, prosaposin, and normal fertilization. Additionally, the mediating effect of prosaposin and semen parameters on the link between pollutants and normal fertilization was investigated. RESULTS: GLM and BKMR showed exposure to ambient air pollutants was all associated with the concentration of seminal prosaposin, among them, O3 and CO were also associated with normal fertilization (-0.10, 95 %CI: -0.13, -0.06; -26.43, 95 %CI: -33.79, -19.07). Among the semen parameters, only the concentration of prosaposin and total motile sperm count (TMC) was associated with normal fertilization (0.059, 95 %CI: 0.047, 0.071; 0.016, 95 %CI: 0.012, 0.020). Mediation analysis showed that prosaposin played a stronger mediating role than TMC in the relationship between short-term exposure to O3 and fertilization (66.83 %, P<0.001 versus 3.05 %, P>0.05). CONCLUSION: Seminal plasma prosaposin showed a stronger meditating effect reflect the correlation between ambient air pollutants and normal fertilization rate than conventional semen parameters, which may be used as one of the indicators between pollution and fertilization in IVF.

Conventional in vitro fertilisation rather than intracytoplasmic sperm injection when only one oocyte is retrieved: Time to overcome irrational fears.

BACKGROUND: The use of intracytoplasmic sperm injection (ICSI) currently extends beyond male factor infertility, notably replacing conventional in vitro fertilisation (IVF) in scenarios like limited oocyte availability, where it is used as a precaution against complete fertilisation failure. While existing studies on the use of conventional IVF in such situations provide some reassurance, the available evidence is somewhat insufficient and ICSI is commonly used. AIMS: To evaluate whether conventional IVF can be a feasible option when only one oocyte is retrieved. MATERIALS AND METHODS: A retrospective study was performed to evaluate the fertilisation rate with conventional IVF in women retrieving only one oocyte and whose partner had normal semen. The study aimed at evaluating whether the fertilisation rate was aligned with the threshold indicated by recognized IVF laboratory performance indicators (Vienna Consensus). Clinical pregnancy and live birth rates were secondary outcomes. RESULTS: Out of 304 cycles with a single oocyte inseminated with conventional IVF, 209 achieved normal fertilisation and 82 did not. Thirteen had no mature oocytes. The fertilisation rate was 69% (95% CI: 63-74%) and increased to 72% (95% CI: 66-77%) when immature oocytes were excluded. The fertilisation rate surpassed the minimum competency threshold of the Vienna Consensus (60%), even if below the benchmark value (75%). Clinical pregnancy and live birth rates per oocyte retrieval were 10% and 8%, respectively. Univariate and multivariate analyses failed to identify any predictive factor of fertilisation. CONCLUSION: Conventional IVF with one oocyte met Vienna Consensus standards even if it fell short of higher benchmarks.

Effect of dietary vitamin E supplement on the reproductive performance and gene expression profiling in Ompok bimaculatus during breeding period.

This study aimed to evaluate the effect of vitamin E on the reproductive responses and the expression of reproductive genes in butter catfish (Ompok bimaculatus). Diets with different levels of vitamin E supplementation (0, 100, and 150 mg/kg) were provided to groups of fish for 60 days. After rearing for 60 days fish were induced with synthetic hormone, that is, Ovatide to study the breeding performance. Ovatide was administrated intramuscularly at the rate of 0.5 and 0.25 mL/kg of body weight for females and males, respectively, in all the treatments. Breeding performance result shows that supplements of vitamin E positively influenced the GSI%, fertilization rate, fecundity, and hatching rate. To understand the relationship between vitamin E and the breeding performance of the fish at the molecular level, a gene expression study was conducted. This study employed real-time PCR for the selected genes critical for reproductive function. In the brain, testis, and ovary dietary vitamin E supplementation of 100 mg/kg significantly enhanced the mRNA transcription of FSHR, Brdt, ESR1, 17beta2, and LHR. Hence, it can be said that 100 mg/kg of vitamin E supplementation in the diet during the reproductive period of O. bimaculatus could improve breeding performance and the mRNA expression of reproductive hormone receptor genes in both males and females of O. bimaculatus.

The expression levels of NOS2, HMOX1, and VEGFC in cumulus cells are markers of oocyte maturation and fertilization rate.

Throughout the reproductive life of women, cumulus cells (CC) protect the dormant oocyte from damage, act as sensors of the follicular microenvironment, and act as a gatekeeper for oocyte developmental potential. One such mechanism relies on the hypoxia-tolerance response, which, with age, decreases systematically, including in the ovary. We aimed to evaluate the association between gene expression related to hypoxia and aging in CC and reproductive results in in vitro fertilization cycles. We recruited 94 women undergoing controlled ovarian stimulation. Total RNA was extracted from pooled CCs collected after oocyte pick-up (OPU) and reverse-transcribed to complementary DNA using random hexamers to test 14 genes related to hypoxia response via HIF1α activation, oxidative stress, and angiogenic responses. The expression of CLU, NOS2, and TXNIP had a positive correlation with age (rs = 0.25, rs = 0.24, and rs = 0.35, respectively). Additionally, NOS2 and HMOX1 expression correlated positively with the retrieval of immature oocytes (rs = 0.22 and rs = 0.40, respectively). Moreover, VEGFC levels decreased overall with increasing fertilization rate, independently of age (rs = -0.29). We found that the fertilization potential of a cohort of oocytes is related to the ability of CC to respond to oxidative stress and hypoxia with age, pointing at NOS2, HMOX1, and VEGFC expression as markers for oocyte maturation and fertilization success.

Common endosymbionts affect host fitness and sex allocation via egg size provisioning.

It is hard to overemphasize the importance of endosymbionts in arthropod biology, ecology and evolution. Some endosymbionts can complement host metabolic function or provide defence against pathogens; others, such as ubiquitous Wolbachia and Cardinium, have evolved strategies to manipulate host reproduction. A common reproductive manipulation strategy is cytoplasmic incompatibility (CI) between differently infected individuals which can result in female mortality or male development of fertilized eggs in haplodiploid hosts. Recently, an additional role of endosymbionts has been recognized in the modification of sex allocation in sexually reproducing haplodiploids. This was theoretically expected due to the maternal inheritance of endosymbionts and natural selection for them to increase infected female production, yet the underlying mechanism remained unknown. Here, we tested whether and how Cardinium and Wolbachia causing different CI types interact to increase female production in a haplodiploid thrips species where sex allocation depends on both maternal condition and egg size provisioning. We found that Cardinium augmented female production by increasing maternal fitness and egg size, thereby boosting fertilization rate and offspring fitness. Wolbachia, in contrast, reduced the beneficial effects of Cardinium. Our results demonstrate different invasion strategies and antagonistic effects of endosymbiotic bacteria on host fitness and evolution of sex allocation.

Double ionophore application in cases with previous failed/low fertilization or poor embryo development.

RESEARCH QUESTION: Does a double ionophore application improve the outcome of cycles in which single ionophore application was unsuccessful? DESIGN: This retrospective intervention study (duration 4.5 years) included 79 patients with suspected chronic failed oocyte activation (<30% fertilizations) and/or poor embryo development (developmental arrest, 24 h developmental delay, blastulation rate <15%) in both preceding cycles, the first without ionophore and the second with single ionophore treatment. Within the study period, all patients with failed ionophore treatments (single applications of ready-to-use calcimycin for 15 min) were offered an adapted protocol in the subsequent cycle (study cycle) in which the same ionophore was applied twice (separated by 30 min). Tests for paired data (control and study cycle) were used to reduce the effect of confounders. RESULTS: The overall fertilization rate did not differ between the study and control cycles. Cleavage (P = 0.020) and blastocyst formation (P = 0.018) rates improved significantly in the study cycles. Implantation (P = 0.001), biochemical (P < 0.001) and clinical pregnancy (P < 0.001) rates were also significantly higher in the study cycles. The study cycles resulted in 29 live births and all 32 babies born were healthy. CONCLUSIONS: This study suggests that double ionophore application may improve blastocyst formation and clinical pregnancy rates in cases of failed single ionophore treatment, irrespective of whether the ionophore was used to overcome fertilization failure or poor embryo development. Fertilization rate was only increased in cases with a history of fertilization failure. Because single ionophore treatment was used in only one previous cycle it cannot be ruled out that some improvement in clinical outcomes would also have been achieved by using single instead of double ionophore treatment again in the subsequent attempt.

Sex-specific differences in reproductive life-history traits of the moss Weissia jamaicensis.

PREMISE: We investigated sex-specific differences in the life-history traits of a metapopulation of the dioicous moss Weissia jamaicensis. Field observations revealed high rates of fertilization, which is uncommon for most dioicous bryophytes. We raised four hypotheses associated with the way the reproductive traits are related to the fertilization rate in this metapopulation. METHODS: We sampled 10 patches of the metapopulation and quantified sexual expression, sex ratio, reproductive success, and reproductive allocation. The ramets were classified as male, non-sporophytic female, sporophytic female, or non-sex-expressing. Thirty ramets from each of the categories expressing sex were placed for regeneration to test the effect of reproductive allocation on this trait. RESULTS: We found greater expression of the female function in all patches, implying a female bias in the metapopulation. The number of male ramets was variable in each patch and did not affect reproductive success. At the prezygotic level, the allocation of resources to the male function was higher. However, the large allocation of resources to sporophyte development in sporophytic females, which exceeded allocations at prezygotic levels, was related to the higher mortality rate of these ramets, suggesting reproductive cost. CONCLUSIONS: The prezygotic ramets that allocated the greatest amount of resources to reproduction expressed sex less frequently, biasing the sex ratio toward the sex that allocated the least amount of resources to reproduction. Overall, the ramets that allocated the greatest amount of resources to reproduction had the lowest regeneration rate, suggesting reproductive cost.

Among high responders, is oocyte development potential different in Rotterdam consensus PCOS vs non-PCOS patients undergoing IVF?

PURPOSE: To evaluate the oocyte potential to develop to blastocyst in Rotterdam consensus PCOS in women with hyper-responses requiring freeze-all embryos. METHODS: Retrospective, single-academic center, cohort study of 205 patients who underwent freeze-all antagonist IVF cycles for OHSS risk between 2013 and 2019. Women in the PCOS group (n = 88) were diagnosed per the 2003 Rotterdam criteria. Control patients (n = 122) had no evidence of hyperandrogenism or menstrual disturbance. Data was compared by t-tests, chi-squared tests, or multivariate logistic regression (SPSS). Frozen blastocysts were Gardner's grade BB or better. RESULTS: There was no difference in terms of number of oocytes collected (PCOS vs non-PCOS 27.7 ± 9.4 vs 25.9 ± 8.2, p = 0.157), number of MII (20.7 ± 8.0 vs 19.1 ± 6.6, p = 0.130), number of 2PN fertilized (15.6 ± 7.4 vs 14.4 ± 5.9, p = 0.220), and number of frozen blastocysts (7.8 ± 4.9 vs 7.1 ± 3.8, p = 0.272). In addition, fertilization rates (74 ± 17% vs 75 ± 17%, p = 0.730), blastulation rates per 2PN (51 ± 25% vs 51 ± 25%, p = 0.869), and blastulation rates per mature oocytes (37 ± 18% vs 37 ± 15%, p = 0.984) were all comparable between PCOS and controls, respectively. Moreover, there was no difference when comparing PCOS and controls in pregnancy rates (45/81 vs 77/122, p = 0.28) and clinical pregnancy rates (34/81 vs 54/122, p = 0.75), respectively. Multivariate logistic regression controlling for confounders failed to alter these results. CONCLUSION: PCOS subjects do not seem to have altered oocyte potential as measured by number of MII oocytes collected, fertilization, and blastulation rates when compared to high-responder controls, with similar magnitude of stimulation.

[Correlation of sperm mitochondrial membrane potential with semen parameters and outcomes of in vitro fertilization].

OBJECTIVE: To investigate the correlation of sperm mitochondrial membrane potential (MMP) with routine semen parameters and the effect of MMP on the outcomes of in vitro fertilization (IVF). METHODS: We retrospectively analyzed the clinical data on 727 IVF cycles, including 231 fresh transplantation cycles, in our hospital from November 2018 to October 2019. According to the MMP level determined by JC-1 staining and flow cytometry, we divided the patients into a low MMP (≤52%) and a high MMP (> 52%) group and compared the rates of fertilization, clinical pregnancy, abortion and live birth between the two groups. Meanwhile, we analyzed the correlation of sperm MMP with the semen volume, sperm concentration, total sperm count, total sperm motility, percentages of progressively motile sperm (PMS) and morphologically normal sperm (MNS), and sperm DNA fragmentation index (DFI). RESULTS: The fertilization rate was significantly higher in the high MMP than in the low MMP group (85.3% ï¼»2 211/2 592ï¼½ vs 81.7% ï¼»3 910/4 785ï¼½, P < 0.01), and so were the rates of clinical pregnancy (50.00% ï¼»41/82ï¼½ vs 48.32% ï¼»72/149ï¼½, P < 0.05) and live birth (43.90%ï¼»36/82ï¼½ vs 40.94% ï¼»61/149ï¼½, P < 0.05), while the abortion rate was lower in the former than in the latter group (12.20% ï¼»5/41ï¼½ vs 15.28% ï¼»11/72ï¼½, P > 0.05). Statistically significant differences were observed between the two groups in sperm concentration, total sperm motility, percentages of PMS and MNS, and sperm DFI (P< 0.05), but not in the semen volume and total sperm count (P > 0.05). Sperm MMP was found correlated positively with sperm concentration (r = 0.11, P < 0.05), total sperm motility (r = 0.304, P < 0.01) and percentages of PMS (r = 288, P < 0.01) and MNS (r = 458, P < 0.01) but negatively with sperm DFI (r = 0.387, P < 0.01). CONCLUSION: The level of sperm MMP is related to decreased sperm motility, increased sperm abnormality, elevated sperm DFI and reduced IVF rate. It is also an important index for sperm function evaluation and, together with routine semen parameters, helps to comprehensively evaluate and optimize the assisted pregnancy program of infertile men in assisted reproduction technology.

Inseminating dose for the artificial fertilization of Brycon amazonicus (Teleostei: Characidae).

Knowledge of the sperm-oocyte ratio in fish fertilization serves as the basis for studies on artificial reproduction and gamete manipulation. The aim of this study was to determine the minimum insemination dose for Brycon amazonicus oocyte fertilization. Female and male gametes were used and tested with the following doses of spermatozoa oocyte-1 ml-1: 10,000, 20,000, 40,000, 60,000 and 80,000 (in triplicate). Fertilization rates were calculated and estimated from the regression equation by applying the segmented regression model 'Linear Response Plateau' to determine the appropriate proportion of gametes. Based on the equation Y = 14.3415 + 0.0007836X, the fertilization rate increased up to 63.34% as it reached a plateau with a proportion of 62,524 spermatozoa oocyte-1 ml-1, which is the minimum insemination dose recommended for artificial insemination of the species.

The effect of rapid and delayed insemination on reproductive outcome in conventional insemination and intracytoplasmic sperm injection in vitro fertilization cycles.

PURPOSE: The precise timing of insemination after oocyte retrieval is sometimes challenging. In this study, we have assessed the effect of the variation in insemination timing on reproductive outcome for both conventional insemination (CI) and intracytoplasmic sperm injection (ICSI) cycles. METHODS: A single-center retrospective cohort data analysis was performed on 6559 patients (9575 oocyte retrievals) from January 2017 to July 2019. The main outcome measured was live birth rates. Secondary outcomes included fertilization rate per all oocytes retrieved, blastocyst utilization, clinical pregnancy, and miscarriage rates. The time interval between oocyte retrieval and insemination was analyzed in eight categories: 0 (0- < 0.5 h), 1 (0.5- < 1.5 h), 2 (1.5- < 2.5 h), 3 (2.5- < 3.5 h), 4 (3.5- < 4.5), 5 (4.5- < 5.5), 6 (5.5-6.5), and 7 (6.5- < 8 h). The number of retrievals in each group (0-7) was 586, 1594, 1644, 1796, 1836, 1351, 641, and 127 respectively. RESULTS: The mean fertilization rate for CI ranged from 54.1 to 64.9% with a significant difference between time categories 0 and 5 (p < 0.001) and 1 and 5 (p < 0.0.001). The mean fertilization rate for ICSI ranged from 52.8 to 67.3% with no significant difference between time categories. Blastocyst rate for CI and ICSI was not significantly different. Miscarriage and clinical pregnancy rates in CI and ICSI were not significantly different. Live birth rates differed significantly (p < 0.05) in CI with time categories 0 and 7 representing the lowest rates, but not in the ICSI group. CONCLUSION: If performing CI or ICSI before 1.5 h and > 6.5 h, any detrimental effects are moderate on fertilization but do not affect blastocyst usage and birth rates. TRIAL REGISTRATION: Institutional Review Board Approval from the Beth Israel Deaconess Medical Centre [IRB Protocol #: 2015P000122].

Lower Spermatozoal PIWI-LIKE 1 and 2 Transcript Levels Are Significantly Associated with Higher Fertilization Rates in IVF.

The four human PIWI-LIKE gene family members PIWI-LIKE 1-4 play a pivotal role in stem cell maintenance and transposon repression in the human germline. Therefore, dysregulation of these genes negatively influences the genetic stability of the respective germ cell and subsequent development and maturation. Recently, we demonstrated that a lower PIWI-LIKE 2 mRNA expression in ejaculated spermatozoa is more frequent in men with oligozoospermia. In this study, we analysed how PIWI-LIKE 1-4 mRNA expression in ejaculated spermatozoa predicts ART outcome. From 160 IVF or ICSI cycles, portions of swim-up spermatozoa used for fertilization were collected, and the total RNA was isolated. PIWI-LIKE 1-4 mRNA expression was measured by qPCR using TaqMan probes with GAPDH as a reference gene. PIWI-LIKE 1 and 2 transcript levels in the spermatozoa of the swim-up fraction were positively correlated to each other (rS = 0.78; p < 0.001). Moreover, lower PIWI-LIKE 2 mRNA levels, as well as lower PIWI-LIKE 1 mRNA levels, in these spermatozoa were positively associated with a fertilization rate ≥ 50% in the respective ART cycles (p = 0.02 and p = 0.0499, Mann-Whitney U-Test). When separately analysing IVF and ICSI cycles, PIWI-LIKE 1 and 2 transcript levels were only significantly associated to increased fertilization rates in IVF, yet not in ICSI cycles. Spermatozoal PIWI-LIKE 3 and 4 transcript levels were not significantly associated to fertilization rates in ART cycles. In conclusion, lower levels of spermatozoal PIWI-LIKE 1 and 2 mRNA levels are positively associated with a higher fertilization rate in IVF cycles.

Performing ICSI within 4 hours after denudation optimizes clinical outcomes in ICSI cycles.

BACKGROUND: The study aimed to investigate whether and how general and partial time intervals between processes, from human chorionic gonadotrophin (HCG) trigger to intracytoplasmic sperm injection (ICSI), affected the laboratory and reproductive outcomes in ICSI cycles. METHODS: This was a retrospective data analysis of 3602 women who underwent ICSI treatment cycles using partner or donor sperms, performed at Reproduction Medicine Center of Tongji Hospital of Tongji Medical College of Huazhong University of Science and Technology (Wuhan, China) between October 2016 and September 2018. The clinical pregnancy rate was the major outcome in the study. The fertilization and available embryo rates were secondary outcomes. RESULTS: Data from 3602 consecutive fresh ICSI cycles was analysed. Multivariate linear regression and logistic regression analysis of factors related to fertilization and clinical pregnancy rates showed that fertilization rate (P = 0.001) and clinical pregnancy rate (P = 0.037) were significantly associated with denudation (DN)-ICSI interval. Long DN-ICSI interval was associated with higher rate of fertilization than short DN-ICSI interval but significantly decreased clinical pregnancy rate when the interval is over 4 h (P < 0.05). CONCLUSIONS: DN-ICSI time interval can act as an independent predictor for clinical outcomes in ICSI cycles. The optimal time for ICSI is within 4 h after oocyte denudation for excellent laboratory and reproductive outcomes in ICSI cycles.

Deletion of c16orf45 in zebrafish results in a low fertilization rate and increased thigmotaxis.

c16orf45 is located at 16p13.11, an important locus related to neurodevelopmental diseases. Clinical studies have demonstrated that c16orf45 is associated with various neurodevelopmental diseases. To further elucidate the effect of c16orf45 on neural development, we constructed a zebrafish model with a stably inherited c16orf45 deletion via CRISPR/Cas9 technology. We found that deletion of c16orf45 significantly reduced the zebrafish fertilization rate, and both females and males showed reduced fertility. Meanwhile, the homozygous c16orf45 knockout zebrafish showed a developmental delay at 24 hr postfertilization (hpf). However, morphological changes were not apparent after 2 days postfertilization (dpf). Notably, the results of behavioral experiments revealed increased thigmotaxis in c16orf45-/- zebrafish at 2 months. In conclusion, these findings demonstrate that c16orf45 plays an important role in nervous system and reproductive system.

Mitochondrial Function in Modulating Human Granulosa Cell Steroidogenesis and Female Fertility.

Ovarian follicle steroidogenesis associated with embryo quality results in a successful pregnancy. Each follicle consists of an oocyte surrounded by granulosa cells, which secrete several steroid and peptide hormones. Follicles harvested from women who conceived after assisted reproductive therapy (ART) had significantly higher estradiol levels in follicular fluids than the follicles from women who failed to conceive after ART. The higher follicular estradiol levels correlate well with successful fertilization following ART. Mitochondria are the central sites for steroid hormone biosynthesis. The first and rate-limiting step in the biosynthesis of steroid hormones occurs in the mitochondria of granulosa cells. In the present study, we hypothesized that the mitochondria in granulosa cells are critical for maintaining oocyte quality and fertility capacity. This study aims to clarify the relationship between mitochondrial function and granulosa cell steroidogenesis, and the relationship between hormone levels and fertility capacity. Sera, follicular fluids and granulosa cells were obtained from individuals undergoing IVF-ET treatment. The oocyte numbers, oocyte quality, fertilization rate, and pregnancy rate were also recorded. The patients who provided the granulosa cells were further classified into four groups: endometriosis, ovarian endometrioma, endometriosis without ovarian endometrioma, and polycystic ovary syndrome (PCOS); patients with other female factor infertility and male factor infertility were used as controls. We measured the levels of estradiol (E2) by radioimmunoassay. Concurrently, we analyzed the mitochondrial mass and membrane potential, and apoptosis by flow cytometry using nonyl acridine orange, TMRE, Annexin V-FITC and PI. Mitochondrial morphology was visualized by transfection with pLV-mitoDsRed. In addition, we assessed the protein levels of steroidogenic enzymes, steroidogenic acute regulatory protein (StAR) and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) by Western blot. The results showed significantly decreased serum E2 and follicular E2 levels, and decreased IVF outcomes, in the patients with endometriosis. Reduced mitochondrial mass and decreased mitochondrial membrane potential were correlated with lower E2. Furthermore, a significant decrease in StAR and 3ß-HSD was found in patients with ovarian endometrioma. The enzyme levels of StAR and 3ß-HSD were highly correlated with E2 levels. Finally, elevated cumulus cell apoptosis was found in the patient group with ovarian endometrioma and PCOS. In conclusion, mitochondrial dysfunction of human granulosa cells may contribute to the decline of steroidogenesis, decreased fertilization rate, oocyte maturation rate, and oocyte quality, and it can ultimately jeopardize fertility.

Comparison of two different oocyte vitrification methods: a prospective, paired study on the same genetic background and stimulation protocol.

STUDY QUESTION: Can two different methods for oocyte vitrification, one using an open tool and the other a closed tool, result in similar oocyte survival rates? SUMMARY ANSWER: The oocyte survival rate was found to be higher in the closed method. WHAT IS KNOWN ALREADY: Open vitrification is performed routinely in oocyte donation cycles. Closed oocyte vitrification may result in slower cooling rates and thus it is less used, even though it has been recommended in order to avoid the risk of cross-contamination between material from different patients. STUDY DESIGN, SIZE, DURATION: This is a prospective cohort study with sibling oocytes carried out in a fertility center between July 2014 and January 2016. The study included 83 oocyte donors each providing a minimum of 12 mature oocytes (metaphase II: MII) at oocyte retrieval. Oocyte survival rate and fertilization rate, as well as reproductive outcomes (biochemical, clinical, ongoing pregnancy and live birth rates) per embryo transfer and also cumulatively between the two methods were compared by Chi2 tests. PARTICIPANTS/MATERIALS, SETTING, METHODS: Donor oocytes were denuded and six MII oocytes from each donor were vitrified using an open method and later assigned to one recipient, while another six MII oocytes were vitrified using a closed method and assigned to a different recipient (paired analysis). ICSI was used in all cases and embryo transfer was performed on Day 2-3 in all cases. MAIN RESULTS AND THE ROLE OF CHANCE: Oocyte donors were 24.8 years old on average (SD 4.7). Recipient age (average 41.2 years, SD 4.7) and BMI (mean 23.8 kg/m2, SD 4.0) were similar between recipient groups. Oocytes vitrified using the closed method had higher survival rate (94.5% versus 88.9%, P = 0.002), but lower fertilization rate (57.1% versus 69.8%, P < 0.001) compared to the open method. The number of fresh embryos transferred in the two groups was 1.8 on average (SD 0.4). Biochemical (45% closed versus 50% open), clinical (40% versus 50%) and ongoing (37.5% versus 42.5%) pregnancy rates were not different between groups (P > 0.05) and neither were live birth rates (37.5% versus 42.5%, P > 0.05). Cumulative reproductive results (obtained after the transfer of all the embryos) were also similar between groups. LIMITATIONS, REASONS FOR CAUTION: The participants of this study were oocyte donors, i.e. young women in good health, and care should be exerted in extending our results to other populations such as infertility patients, oncofertility patients and women freezing oocytes to delay childbearing. WIDER IMPLICATIONS OF THE FINDINGS: Our results suggest that, in spite of different survival and fertilization rates, closed and open oocyte vitrification methods should offer similar reproductive outcomes up to cumulative live birth rates. STUDY FUNDING/COMPETING INTEREST(S): The authors report no conflict of interest. Vitrolife provided the media and the closed method tool needed for the study at no cost.