Embryo Transfer Strategies for Women with Recurrent Implantation Failure During the Frozen-thawed Embryo Transfer Cycles:Sequential Embryo Transfer or Double-blastocyst Transfer?

Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of SeET and DBT on pregnancy outcomes.Methods Totally,261 frozen-thawed embryo transfer cycles of 243 RIF women were included in this multicenter retrospective analysis.According to different embryo quality and transfer strategies,they were divided into four groups:group A,good-quality SeET(GQ-SeET,n=38 cycles);group B,poor-quality or mixed-quality SeET(PQ/MQ-SeET,n=31 cycles);group C,good-quality DBT(GQ-DBT,n=121 cycles);and group D,poor-quality or mixed-quality DBT(PQ/MQ-DBT,n=71 cycles).The main outcome,clinical pregnancy rate,was compared,and the generalized estimating equation(GEE)model was used to correct potential confounders that might impact pregnancy outcomes.Results GQ-DBT achieved a significantly higher clinical pregnancy rate(aOR 2.588,95%CI 1.267–5.284,P=0.009)and live birth rate(aOR 3.082,95%CI 1.482–6.412,P=0.003)than PQ/MQ-DBT.Similarly,the clinical pregnancy rate was significantly higher in GQ-SeET than in PQ/MQ-SeET(aOR 4.047,95%CI 1.218–13.450,P=0.023).The pregnancy outcomes of GQ-SeET were not significantly different from those of GQ-DBT,and the same results were found between PQ/MQ-SeET and PQ/MQ-DBT.Conclusion SeET relative to DBT did not seem to improve pregnancy outcomes for RIF patients if the embryo quality was comparable between the two groups.Better clinical pregnancy outcomes could be obtained by transferring good-quality embryos,no matter whether in SeET or DBT.Embryo quality plays a more important role in pregnancy outcomes for RIF patients.

Kidding after Transfer of in Vitro Produced Saanen Goat Embryos into Local Ukrainian Breed Recipients in Different Seasons

In recent years, the demand for goat products has been growing due to the fact that goat milk has a number of advantages over cow milk, for example, it is low in lactose, and is considered less allergenic and easier to digest. To increase production during both breeding and non-breeding seasons and reduce the price of dairy products, it is necessary to effectively use reproductive management and assisted reproductive technologies. In vitro embryo production makes it possible to obtain a large number of eggs from goats, which for some reason are unable to conceive, but have genetic value. Afterward in vitro produced embryos can be transferred into recipient goats of other less genetically valuable breeds, such as the Ukrainian local breed. Therefore, the aim of the present study was to investigate the effectiveness of transfers of in vitro produced embryos of Saanen goats into surrogate sires of the Ukrainian local breed in different seasons. All manipulations with animals were carried out following ethical standards (Strasbourg, 1986). Six Saanen goats were selected as the oocyte donors. After the hormonal stimulation oocytes were retrieved by laparoscopic ovum pick-up. In vitro produced embryos were transferred laparotomically into 24 recipients of Ukrainian local breed. Fifty days after embryo transfers, pregnancies were determined by ultrasound diagnostics. Although the embryo development rate in the breeding season was 20% higher than in the non-breeding season, there was no difference in pregnancy and kidding rates between seasons. In conclusion, the transfer of in vitro produced Saanen goat embryos to recipients of the Ukrainian local breed gives the opportunity to achieve pregnancy and kidding regardless of the breeding season, which will enable a faster and more efficient increase in the livestock of highly productive goats in Ukraine in the post-war period.

Is the Mock Transfer Enough Reliable to Evaluate Hysterometry for Embryo Transfer?

Objectives: The aim of this study was to assess the reliability of the mock transfer during in vitro fertilization process Method: A case-control study was conducted on 134 patients included in IVF/ICSI cycles. From the hysterometry obtained during the mock transfer, the ideal embryo replacement site, i.e. two cm from the uterine fundus has been determined. Results: Significant differences were noted between the area estimated from the mock transfer and the area where the embryo was deposited during the actual embryo transfer. In fact, 15.9% of the patients had a difference between four and six cm, and 32% of the patients returning for a subsequent transfer had at least 2 cm of difference between the embryo deposit zones. This difference was significant (P 0.00) Conclusion: More than ultrasound guidance, the challenge with embryo transfer is to be able to minimize variations in the length of the uterus. This would make it possible to determine the ideal transfer depot area without multiple manipulations.

The Clinical Outcomes of Mosaic Embryo Transfer in Preimplantation Genetic Testing Cycles

Purpose: We aimed to analyze the pregnancy outcomes and perinatal follow-up of mosaic embryo transfer in the preimplantation genetic testing (PGT) cycles. Method: We retrospectively selected 27 mosaic embryo transfer cycles as the study group and 97 euploid embryo transfer cycles as the control group after propensity score matching, which were performed in the reproductive medicine center of the Sixth Affiliated Hospital, Sun Yat-sen University, from March 2019 to September 2023. The biopsy cells from blastocyst were undertaken next generation sequencing (NGS). Results: No significant difference in pregnancy outcomes compared between the two groups. According to the size of aneuploid, fragment the level of mosaicism or blastocyst morphological gradings, there were no significant difference in mosaic embryo transfers. Conclusion: Mosaic embryo detected in the PGT cycle can lead to clinical pregnancy and live birth of healthy offspring, which can be considerate suitable for transfer.

Pregnancy Outcomes for Day 5 Versus Day 6 Single Frozen-thawed Blastocyst Transfer with Different Qualities of Embryos: A Large Matched-cohort Study

Objective This study aimed to determine whether the day of blastocyst expansion affects pregnancy outcomes in frozen-thawed blastocyst transfer(FBT)cycles.Methods A retrospective match-cohort study was conducted.Patients who underwent blastocyst transfer in frozen-thawed cycles at day 5 or 6 were matched for potential confounding factors.A total of 2207 matched pairs of FBT cycles were included from January 2016 to December 2019 in our Reproductive Medicine Center.Results The clinical pregnancy rate(CPR)and live birth rate(LBR)were significantly increased in day 5 blastocyst transfers when compared to day 6 blastocyst transfers,in terms of the same embryo quality.For FBT cycles with good-quality embryo,the CPR at day 5 and 6 was 61.30%and 57.56%,respectively(P=0.045),and the LBR was 44.79%and 36.16%,respectively(P<0.001).For FBT cycles with poor-quality embryo,the CPR at day 5 and 6 was 48.61%and 40.89%,respectively(P=0.006),and the LBR was 31.71%and 25.74%,respectively(P=0.019).The CPR for FBT cycles with good-quality embryo was statistically higher at day 6 than that at day 5 with poor-quality embryo transferred(57.56%vs.48.61%,P=0.001).Maternal age,anti-Müllerian hormone(AMH),endometrial thickness,embryo quality,and the day of blastocyst expansion were independently correlated with the CPR and LBR.The FBT cycles at day 5 had significantly higher CPR(adjusted odds ratio[OR]=1.246,95%confidence intervals[CI]:1.097–1.415,P=0.001)and LBR(adjusted OR=1.435,95%CI:1.258–1.637,P<0.001)than those at day 6.Conclusion The embryo quality is the primary indicator for FBT cycles.Day 5 blastocysts should be preferred when the quality of embryo at day 5 is the same as that at day 6.

Live births from in vitro fertilization-embryo transfer following the administration of gonadotropin-releasing hormone agonist without gonadotropins:Two case reports

BACKGROUND The prevalence of female infertility between the ages of 25 and 44 is 3.5%to 16.7%in developed countries and 6.9%to 9.3%in developing countries.This means that infertility affects one in six couples and is recognized by the World Health Organization as the fifth most serious global disability.The International Committee for Monitoring Assisted Reproductive Technology reported that the global total of babies born as a result of assisted reproductive technology procedures and other advanced fertility treatments is more than 8 million.Advancements in controlled ovarian hyperstimulation procedures led to crucial accomplishments in human fertility treatments.The European Society for Human Reproduction and Embryology guideline on ovarian stimulation gave us valuable evidence-based recommendations to optimize ovarian stimulation in assisted reproductive technology.Conventional ovarian stimulation protocols for in vitro fertilization(IVF)–embryo transfer are based upon the administration of gonadotropins combined with gonadotropin-releasing hormone(GnRH)analogues,either GnRH agonists(GnRHa)or antagonists.The development of ovarian cysts requires the combination of GnRHa and gonadotropins for controlled ovarian hyperstimulation.However,in rare cases patients may develop an ovarian hyper response after administration of GnRHa alone.CASE SUMMARY Here,two case studies were conducted.In the first case,a 33-year-old female diagnosed with polycystic ovary syndrome presented for her first IVF cycle at our reproductive center.Fourteen days after triptorelin acetate was administrated(day 18 of her menstrual cycle),bilateral ovaries presented polycystic manifestations.The patient was given 5000 IU of human chorionic gonadotropin.Twenty-two oocytes were obtained,and eight embryos formed.Two blastospheres were transferred in the frozen-thawed embryo transfer cycle,and the patient was impregnated.In the second case,a 37-year-old woman presented to the reproductive center for her first donor IVF cycle.Fourteen days after GnRHa administration,the transvaginal ultrasound revealed six follicles measuring 17-26 mm in the bilateral ovaries.The patient was given 10000 IU of human chorionic gonadotropin.Three oocytes were obtained,and three embryos formed.Two high-grade embryos were transferred in the frozen-thawed embryo transfer cycle,and the patient was impregnated.CONCLUSION These two special cases provide valuable knowledge through our experience.We hypothesize that oocyte retrieval can be an alternative to cycle cancellation in these conditions.Considering the high progesterone level in most cases of this situation,we advocate freezing embryos after oocyte retrieval rather than fresh embryo transfer.

Pregnancy outcomes following supplementation of single dose GnRH agonist to sustain the luteal phase in antagonist fresh embryo transfer cycles:A multicentric prospective cohort study

Objective:To determine whether a single dose of gonadotropin-releasing hormone(GnRH)agonist administered subcutaneously in addition to the regular progesterone supplementation could provide a better luteal support in antagonist protocol fresh embryo transfer cycles.Methods:This prospective,multicentric,cohort study included total 140 women,70 in each group.Controlled ovarian stimulation was carried out as per fixed GnRH antagonist protocol.The trigger was given with hCG.In vitro fertilization/intracytoplasmic sperm injection(IVF/ICSI)was performed and day-3 embryos were transferred.Patients were divided into groups 1 and 2 based on computer generated randomization sheet.Six days following oocyte retrieval,group 1 received 0.2 mg decapeptyl subcutaneously in addition to regular progesterone support while group 2 received progesterone only.Luteal support was given for 14 days to both groups;if pregnancy was confirmed luteal support was continued till 12 weeks of gestation.The clinical pregnancy rate was the primary outcome.The implantation rate,miscarriage rate,live birth delivery rate,and multiple pregnancy rates were the secondary outcomes.Results:A total of 140 patients were analysed,70 in each group.Clinical pregnancy rates(47.1%vs.35.7%;P=0.17),implantation rates(23.4%vs.18.1%,P=0.24),live birth delivery rates(41.4%vs.27.1%,P=0.08),and multiple pregnancy rates(21.2%vs.16.0%,P=0.74)were higher in group 1 than in group 2.Group 1 had a lower miscarriage rate than group 2(5.7%vs.8.6%;P=0.75).However,these differences were not statistically significant between the two groups.Conclusions:Administration of a single dose of GnRH agonist in addition to regular natural micronized vaginal progesterone as luteal support in GnRH antagonist protocol cycles marginally improves implantation rates,clinical pregnancy rates,and live birth delivery rates.However,more studies with higher sample sizes are needed before any conclusive statements about GnRH agonist as luteal phase support can be made.

Clinical validation of the early embryo viability assessment system: Analysis for the blastocyst morphology and pregnancy outcomes

Objective:To determine the relationship between the early embryo viability assessment(EEVA)and blastocyst morphological parameters and pregnancy outcomes.Methods:This retrospective cohort study was conducted on 291 intracytoplasmic sperm injection cycles including 2522 embryos with indications of prolonging embryo culture to the blastocyst stage in the Genea embryo review incubator,and 511 single vitrified-warmed blastocyst transfer cycles from January 2020 to June 2023.The EEVA system produced an EEVA score from E1(best)to E5(worse)for the potential of blastocyst formation.Blastocyst morphology was evaluated.The association between the EEVA score and each type of blastocyst morphology,implantation rate,clinical pregnancy,and ongoing pregnancy were assessed using generalized estimating equations.Results:The inner cell mass A(ICM A),trophectoderm A(TE A),blastocoele expansion degree of 3,4,5,6,7 rates were higher with lower the EEVA score.The adjusted odd ratio(aOR)(E5 vs E1)was 0.3 for ICM A,0.174 for TE A and 0.210 for BL3,4,5,6,7(all P<0.001),suggesting a significant association between lower EEVA scores and improved embryo quality.The implantation,clinical pregnancy,and ongoing pregnancy rate were also higher with lower the EEVA score.The aOR of E5 vs E1 was 0.245 for implantation,0.185 for clinical pregnancy and 0.200 for ongoing pregnancy rate(P<0.001).Conclusions:There were associations between blastocyst morphology,pregnancy outcome and EEVA scores.The good blastocyst morphology and pregnancy outcomes are higher with lower the EEVA score.

Endochondral ossification of hindlimbs in embryonic development of Japanese Quail(Coturnix japonica)

The endochondral ossification of hindlimb is essential to a bird’s ability to stand,walk and fly.Most hindlimb is ossified in the embryos before hatching in precocial birds.However,the molecular mechanisms of hindlimb ossification in birds is still unclear.Therefore,we tried to examine the process of hindlimb ossification and its molecular regulation by using an animal model—Japanese Quail(Coturnix japonica).We selected four critical stages(Embryo Day:E6,E8,E12 and E16) of skeletal development of embryonic quails for hindlimb skeleton staining to show the process of endochondral ossification and to examine the molecular regulation of endochondral osteogenesis by RNA-Seq analysis.The results showed that ossification became increased with embryonic development and most hindlimb was ossified before hatching.RNA-Seq analysis revealed that various signaling pathways were involved with endochondral ossification with thyroid hormone signaling and WNT signaling pathway particularly enriched.Moreover,the expression levels of 42 genes were continuously upregulated and 14 genes were continuously downregulated from E6 to E16.The present study might provide new insights into complex molecular mechanisms in regulation of endochondral ossification.

Embryonic thermal manipulation:a potential strategy to mitigate heat stress in broiler chickens for sustainable poultry production

Due to high environmental temperatures and climate change, heat stress is a severe concern for poultry health and production, increasing the propensity for food insecurity. With climate change causing higher temperatures and erratic weather patterns in recent years, poultry are increasingly vulnerable to this environmental stressor. To mitigate heat stress, nutritional, genetic, and managerial strategies have been implemented with some success. However, these strategies did not adequately and sustainably reduce the heat stress. Therefore, it is crucial to take proactive measures to mitigate the effects of heat stress on poultry, ensuring optimal production and promoting poultry well-being. Embryonic thermal manipulation(TM) involves manipulating the embryonic environment's temperature to enhance broilers' thermotolerance and growth performance. One of the most significant benefits of this approach is its cost-effectiveness and saving time associated with traditional management practices. Given its numerous advantages, embryonic TM is a promising strategy for enhancing broiler production and profitability in the poultry industry. TM increases the standard incubation temperature in the mid or late embryonic stage to induce epigenetic thermal adaption and embryonic metabolism. Therefore, this review aims to summarize the available literature and scientific evidence of the beneficial effect of pre-hatch thermal manipulation on broiler health and performance.

tRNA^(Glu)-derived fragments from embryonic extracellular vesicles modulate bovine embryo hatching

Transfer RNA-derived small RNAs(tsRNAs)have been shown to be involved in early embryo development and repression of endogenous retroelements in embryos and stem cells.However,it is unknown whether tsRNAs also regulate embryo hatching.In this study,we mined the sequencing data of a previous experiment in which we demonstrated that the microRNA(miRNA)cargo of preimplantation embryonic extracellular vesicles(EVs)influences embryo development.We thus profiled the tsRNA cargo of EVs secreted by blastocysts and non-blastocysts.The majority of tsRNAs was identified as tRNA halves originating from the 5'ends of tRNAs.Among the 148 differentially expressed tsRNAs,the 19 nt tRNA fragment(tRF)tDR-14:32-Glu-CTC-1 was found to be significantly up-regulated in EVs derived from non-blastocysts.RT-qPCR assays confirmed its significant up-regulation in non-blastocyst embryos and their conditioned medium compared to the blastocyst group(P<0.05).Inhibition of tDR-14:32-Glu-CTC-1 by supplementing antagomirs to the conditioned medium improved embryo hatching(P<0.05).Transcriptomic analysis of embryos treated with tDR-14:32-Glu-CTC-1 antagomirs further showed differential expression of genes that are associated with embryo hatching and implantation.In summary,tDR-14:32-Glu-CTC-1 is up-regulated in non-blastocyst embryos and their secretions,and inhibition of tDR-14:32-Glu-CTC-1 promotes embryo hatching,while influencing embryo implantation-related genes and pathways.These results indicate that embryonic EVs containing specific tRFs may regulate preimplantation embryo development.

Pre-existing orthorhombic embryos-induced hexagonal-orthorhombic martensitic transformation in MnNiSi_(1-x)(CoNiGe)_x alloy

The thermal-elastic martensitic transformation from high-temperature Ni_(2)In-type hexagonal structure to low-temperature TiNiSi-type orthorhombic structure has been widely studied in MnMX(M=Ni or Co,and X=Ge or Si)alloys.However,the answer to how the orthorhombic martensite nucleates and grows within the hexagonal parent is still unclear.In this work,the hexagonal-orthorhombic martensitic transformation in a Co and Ge co-substituted MnNiSi is investigated.One can find some orthorhombic laths embedded in the hexagonal parent at a temperature above the martensitic transformation start temperature(M_(s)).With the the sample cooing to M_(s),the laths turn broader,indicating that the martensitic transformation starts from these pre-existing orthorhombic laths.Microstructure observation suggests that these pre-existing orthorhombic laths do not originate from the hexagonal-orthorhombic martensitic transformation because of the difference between atomic occupations of doping elements in the hexagonal parent and those in the preexisting orthorhombic laths.The phenomenological crystallographic theory and experimental investigations prove that the pre-existing orthorhombic lath and generated orthorhombic martensite have the same crystallography relationship to the hexagonal parent.Therefore,the orthorhombic martensite can take these pre-existing laths as embryos and grow up.This work implies that the martensitic transformation in MnNiSi_(1-x)(CoNiGe)_(x) alloy is initiated by orthorhombic embryos.

Effect of coenzyme Q10 supplementation on post-vitrification mouse embryo development

Objective:To investigate the effects of coenzyme Q10(CoQ10)supplementation on post-vitrification embryo development and gross morphology.Methods:Balb/c mouse embryos were cultured in potassium simplex optimised medium(KSOM)with varying CoQ10 concentrations[0(control),20,40,and 60μM].The most effective CoQ10 concentration(40μM)was selected for subsequent post-vitrification morphology study.Embryos were randomly divided into four groups:Group A(non-vitrified without CoQ10),Group B(non-vitrified with CoQ10),Group C(vitrified without CoQ10),and Group D(vitrified with CoQ10),followed by vitrification at the 8-cell stage.Survival rates and development until the blastocyst stage were evaluated through morphological examinations using ASEBIR's system,distinguishing normal and abnormal embryos.Results:Supplementation of 40μM CoQ10 significantly increased blastocyst formation(95%)compared to the control group(92%),20μM(62%),and 60μM(56%)(P<0.001).Following vitrification,Group D exhibited a significant increase in blastocyst formation(92%)compared to Group C(82%)(P<0.05).Morphological assessments indicated superior embryo quality in Group B over Group D during the cleavage stage,morula,and blastocyst(P<0.05).Conclusions:CoQ10 supplementation exhibits promising potential to enhance preimplantation embryo development,increase blastocyst formation rates,and improve embryo quality post-vitrification.This offers a promising approach to mitigate oxidative stress on embryos,potentially improving overall assisted reproductive technology outcomes.

A New Micropropagation Technology of Tilia amurensis:In VitroMicropropagation of Mature Zygotic Embryos and the Establishment of a PlantRegeneration System

Tilia amurensis is an economically valuable broadleaf tree species in Northeast China.The production of highqualityT.amurensis varieties at commercial scales has been greatly limited by the low germination rates.Thereis thus a pressing need to develop an organogenesis protocol for in vitro propagation of T.amurensis to alleviate ashortage of high-quality T.amurensis seedlings.Here,we established a rapid in vitro propagation system forT.amurensis from mature zygotic embryos and analyzed the effects of plant growth regulators and culture mediain different stages.We found that Woody plant medium(WPM)was the optimal primary culture medium formature zygotic embryos.The highest callus induction percentage(68.76%)and number of axillary buds induced(3.2)were obtained in WPM+0.89μmol/L 6-benzyladenine(6-BA)+0.46μmol/L kinetin(KT)+0.25μmol/Lindole-3-butryic acid(IBA)+1.44μmol/L gibberellin A_(3)(GA_(3)).The multiple shoot bud development achievedthe highest percentage(83.32%)in the Murashige and Skoog(MS)+2.22μmol/L 6-BA+0.25μmol/L IBA+1.44μmol/L GA_(3).The rooting percentage(96.70%)was highest in 1/2 MS medium+1.48μmol/L IBA.Thesurvival percentage of transplanting plantlets was 82.22%in soil:vermiculite:perlite(5:3:1).Our study is the firstto establish an effective organogenesis protocol for T.amurensis using mature zygotic embryos.

Enhancement of porcine in vitro embryonic development through luteolin‑mediated activation of the Nrf2/Keap1 signaling pathway

Background Oxidative stress,caused by an imbalance in the production and elimination of intracellular reactive oxygen species(ROS),has been recognized for its detrimental effects on mammalian embryonic development.Luteolin(Lut)has been documented for its protective effects against oxidative stress in various studies.However,its specific role in embryonic development remains unexplored.This study aims to investigate the influence of Lut on porcine embryonic development and to elucidate the underlying mechanism.Results After undergoing parthenogenetic activation(PA)or in vitro fertilization,embryos supplemented with 0.5μmol/L Lut displayed a significant enhancement in cleavage and blastocyst formation rates,with an increase in total cell numbers and a decrease in the apoptosis rate compared to the control.Measurements on D2 and D6 revealed that embryos with Lut supplementation had lower ROS levels and higher glutathione levels compared to the control.Moreover,Lut supplementation significantly augmented mitochondrial content and membrane potential.Intriguingly,activation of the Nrf2/Keap1 signaling pathway was observed in embryos supplemented with Lut,leading to the upregulation of antioxidant-related gene transcription levels.To further validate the relationship between the Nrf2/Keap1 signaling pathway and effects of Lut in porcine embryonic development,we cultured PA embryos in a medium supplemented with brusatol,with or without the inclusion of Lut.The positive effects of Lut on developmental competence were negated by brusatol treatment.Conclusions Our findings indicate that Lut-mediated activation of the Nrf2/Keap1 signaling pathway contributes to the enhanced production of porcine embryos with high developmental competence,and offers insight into the mechanisms regulating early embryonic development.

Effect of Mitochondrial Function of Ovarian Granulosa Cells on In Vitro Fertilization and Embryo Transfer Outcomes in Obese Polycystic Ovary Syndrome Patients

Objective:To investigate the effect of abnormal ovarian granulosa cell metabolism on in vitro fertilization and embryo transfer(IVF-ET)outcomes in obese polycystic ovary syndrome(PCOS)patients.Methods:Patients with PCOS who met the study criteria were screened according to the inclusion criteria.A total of 32 patients with obese PCOS were recruited into the study group,and 39 patients with non-obese PCOS were recruited into the control group.The general data(age,body mass index,and years of infertility),insulin resistance index(HOMA-IR),follicle-stimulating hormone(FSH),luteinizing hormone(LH),granulosa cell mitochondrial function,and IVF-ET outcome of patients in the study group and control group were retrospectively analyzed.Results:The differences in age and years of infertility between the study group and the control group were insignificant(P>0.05),and the body mass index(BMI)of the study group and control group was 30.5±1.24 kg/m2 and 22.3±1.12 kg/m2,respectively,in which the difference was statistically significant(P<0.05);the HOMA-IR of the study group was significantly higher than that of the control group(P<0.05);the reactive oxygen species(ROS)in the study group was significantly higher than that in the control group(P<0.05),and the ATP content in the study group was significantly lower than that in the control group(P<0.05);comparing the FSH and LH levels between the two groups,the difference was not statistically significant(P>0.05);the rate of IVF-ET failure was significantly higher in the study group than in the control group.Conclusion:PCOS is a complex endocrine disorder,and obesity is one of the independent risk factors for the development of PCOS.

Effect of Insulin-Transferrin-Selenium on Goat Oocytes Maturation and Embryo Development

[Objective] The research aimed to enhance culture efficiencies of oocyte and embryo of goat in vitro and to explore serum-free culture system in vitro.[Method] At present,the conventional solutions of oocyte maturation and embryo development in vitro were always added into 1% ITS(Insulin-transferrin-selenium) or using 1% ITS to replace FBS in 2 kinds culture solutions for conducting in vitro cultures of goat oocyte and parthenogenetic embryo.The influences of ITS on their developments were detected.[Result] ITS in maturation liquid of oocytes could not increase oocytes maturation rate but significantly increased blastocyst rate (58.06% vs. 48.19%)of parthenogenetic embryo.If FBS in maturation liquid of oocytes was replaced by ITS, the maturation rate, cleavage rate and blastocyst rate were basically unchanged.Adding ITS into embryo medium could increase blastocyst rate (68.30% vs. 56.82%)of parthenogenetic embryo of goat.If FBS in embryo medium was replaced by ITS,the cleavage rate didn’t change basically,while the blastocyst rate in ITS was obviously lower than that in FBS group(42.33% vs.56.82%).[Conclusion] ITS could promote maturation of oocyte in vitro and early embryonic development, in addition,ITS could replace serum in maturation medium of oocyte as serum-free culture system for conducting relevant researches.

Gene Transfer into Young Embryos via Electroporation and Regeneration of Plantlets in Rice

Green fluorescent protein ( GFP ) gene was expressed transiently in 2-3 d old rice embryos by electroporation with the aid of a specially designed loading net. Under suitable conditions (500 μF capacitance, 300 V/cm Voltage, 100 μg/mL plasmid DNA), the percentage of embryos expressing GFP was up to 35%. The highest electroporation efficiency (40%) was obtained at pH 5.8 of the electroporation buffer. The GFP gene driven by the Ubi promoter produced the highest efficiency. Thus, on the basis of optimizing electroporation conditions, a transformation system has been developed for young embryos in rice. The electroporated 4-6 d old embryos regenerated plantlets under the controlled cultural conditions. Fluorescence microscopic observations indicated that GFP gene expressed in their calli and R0 plantlets.

Asynchronous Embryo Transfer in Sheep:Lack of Survival in Progestinized Recipient Ewes

Synchronization of development between the embryo and uterus is required for successful pregnancy establishment. Transfer of early embryos requires synchrony with the recipient uterus of 2 days or less in sheep, because asynchrony of 3 days or more results in failure of pregnancy recognition signaling for maintenance of corpus luteum （CL） and progesterone （P4） production and/or uterine support of the embryo. The objective was to determine if P4 treatment of recipient ewes would obviate the need for pregnancy recognition signaling and maintain a uterine environment conducive to embryo survival after asynchronous transfer, thereby establishing a universal recipient. Embryos （morulae/blastocysts） were recovered on day 6 from super-ovulated donor ewes. Recipient ewes received 25 mg P4 daily from day 6 post-estrus until 60 days after embryo transfer. Embryos were transferred into recipients on day 6,9, 12,18, or 30 post-estrus. The pregnancy rate on day 22 post-transfer was 60% for synchronous transfers to day 6 ewes, 44% and 22% for asynchronous transfers to day 9 and 12 ewes, and 0% for asynchronous transfers to day 18 and 30 ewes. On day 39 posttransfer ,pregnancy rates remained 60% for day 6 ewes,33% for day 9 ewes,and 0% for day 12,18, and 30 ewes. The P4 treatment did extend the window of uterine receptivity to early embryos in ewes by one day ,but did not create a universal recipient. Available results support the idea that a window of uterine receptivity to the conceptus exists in sheep that is independent of pregnancy recognition signaling.

Artificial Cycle with or without a Depot Gonadotropin-releasing Hormone Agonist for Frozen-thawed Embryo Transfer： An Assessment of Infertility Type that Is Most Suitable

The clinical outcomes of five groups of infertility patients receiving frozen- thawed, cleavage-stage embryo transfers with exogenous hormone protocols with or without a depot gonadotropin-releasing hormone （GnRH） agonist were assessed. A retrospective cohort analysis was performed on 1003 cycles undergoing frozen-thawed, cleavage-stage embryo transfers from January 1, 2012 to June 31, 2015 in the Reproductive Medicine Center of Wuhan General Hospital of Guangzhou Military Region. Based on the infertility etiologies of the patients, the 1003 cycles were divided into five groups： tubal infertility, polycystic ovary syndrome （PCOS）, endometriosis, male infertility, and unexplained infertility. The main outcome was the live birth rate. Two groups were set up based on the intervention： group A was given a GnRH agonist with exogenous estrogen and progesterone, and group B （control group） was given exogenous estrogen and progesterone only. The results showed that the baseline serum hormone levels and basic characteristics of the patients were not significantly different between groups A and B. The live birth rates in groups A and B were 41.67% and 29.29%, respectively （P〈0.05）. The live birth rates in patients with PCOS in groups A and B were 56.25% and 30.61%, respectively （P〈0.05）. The clinical pregnancy, implantation and on-going pregnancy rates showed the same trends as the live birth rates between groups A and B. The ectopic pregnancy rate was significantly lower in group A than in group B. We concluded that the live birth rate was higher and other clinical outcomes were more satisfactory with GnRH agonist co- treatment than without GnRH agonist co-treatment for frozen-thawed embryo transfer. The GnRH agonist combined with exogenous estrogen and progesterone worked for all types of infertility tested, especially for women with PCOS.