Microfluidic thermotaxic selection of highlymotile sperm and in vitro fertilization

The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing intensely rely on centrifugation and wash steps that may induce mechanical damage and oxidative stress to sperm.Although a few microfluidic sperm sorting devices may avoid these adverse effects by exploiting intrinsic guidance mechanisms of sperm swimming,none of these approaches have been fully validated by clinical-grade assessment criteria.In this study,a microfluidic sperm sorting device that enables the selection of highly motile and functional sperm via their intrinsic thermotaxis is presented.Bioinspired by the temperature microenvironment in the fallopian tube during natural sperm selection,a microfluidic device with controllable temperature gradients along the sperm separation channel was designed and fabricated.This study investigated the optimal temperature conditions for human sperm selection and fully characterized thermotaxis-selected sperm with 45 human sperm samples.Results indicated that a temperature range of 35–36.5℃along the separation channel significantly improves human sperm motility rate((85.25±6.28)%vs.(60.72±1.37)%;P=0.0484),increases normal sperm morphology rate((16.42±1.43)%vs.(12.55±0.88)%;P<0.0001),and reduces DNA fragmentation((7.44±0.79)%vs.(10.36±0.72)%;P=0.0485)compared to the nonthermotaxis group.Sperm thermotaxis is species-specific,and selected mouse sperm displayed the highest motility in response to a temperature range of 36–37.5℃ along the separation channel.Furthermore,IVF experiments indicated that the selected sperm permitted an increased fertilization rate and improved embryonic development from zygote to blastocyst.This microfluidic thermotaxic selection approach will be translated into clinical practice to improve the IVF success rate for patients with oligozoospermia and asthenozoospermia.

Association between Exposure of Rare Earth Elements and Outcomes of In Vitro Fertilization-Embryo Transfer in Beijing

Objective The study aimed to investigate the impact of rare earth elements(REEs)exposure on pregnancy outcomes of in vitro fertilization-embryo transfer(IVF-ET)by analyzing samples from spouses.Methods A total of 141 couples were included.Blood and follicular fluid from the wives and semen plasma from the husbands,were analyzed for REEs using inductively coupled plasma mass spectrometry(ICP-MS).Spearman's correlation coefficients and the Mann–Whitney U test were used to assess correlations and compare REE concentrations among three types of samples,respectively.Logistic models were utilized to estimate the individual REE effect on IVF-ET outcomes,while BKMR and WQS models explored the mixture of REE interaction effects on IVF-ET outcomes.Results Higher La concentration in semen(median 0.089 ng/mL,P=0.03)was associated with a lower fertilization rate.However,this effect was not observed after artificial selection intervention through intracytoplasmic sperm injection(ICSI)(P=0.27).In semen,the REEs mixture did not exhibit any significant association with clinical pregnancy.Conclusion Our study revealed a potential association between high La exposure in semen and a decline in fertilization rate,but not clinical pregnancy rate.This is the first to report REEs concentrations in follicular fluid with La,Ce,Pr,and Nd found at significantly lower concentrations than in serum,suggesting that these four REEs may not accumulate in the female reproductive system.However,at the current exposure levels,mixed REEs exposure did not exhibit reproductive toxicity.

The barriers of joining in vitro fertilization programs among infertile couples in developing countries:A scoping review

Objective:To determine the barriers of joining in-vitro fertilization(IVF)programs among infertile couples in developing countries.Methods:This study assessed infertile couples and the barriers or associated factors resulting in delayed decision-making of joining IVF program by searching databases PubMed,ScienceDirect,EBSCO,ClinicalKey,and Cochrane Library from inception until December 31,2021.Additional search strategies were snowballing literature search and citation tracking.Results:Eleven articles were included in the scoping review.The cost was the greatest barrier of joining IVF program.Limited access and lack of assisted reproductive technology centers,few qualified infertility trained staff,insufficient government support,low priority in government policy,along with sociocultural factors,such as religion and false beliefs or myths were also majorly considered to be associated obstacles.Conclusions:The main barrier associated with IVF program among infertile couples in developing countries is the high cost of the IVF services.

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.

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.

Effects of Cumulus Cells on in vitro Fertilization of Bovine

[Objective] The aim was to explore the effect of cumulus cells on the in vitro fertilization of in vitro matured bovine oocytes. [Method] The in vitro matured oocytes were divided into three groups of cumulus cells removal, partial removal and no removal. [Result] In the co-culture with cumulus cells, the oocytes of the removal group had higher cleavage rate and blastocyst rate （74.4%±4.1, 53.7%±5.1） than those of the no removal group （72.7%±5.1, 52.4%±3.5）, but the difference was not significant （P〉0.05）, while both groups had better performances than the re- moval group （39.6%±4.5, 18.8%±4.6） with the difference reaching the significant level （P〈0.05）. All the three groups showed significant difference with the control. The combination of cumulus cells and melatonin achieved the best effects as the cleavage rate and blastocyst rate of the partial removal group （79.8%±3.7, 56.5%±5.1） were better than those of the no removal group （78.2%±2.6, 55.8%±4.6）, and the difference was not significant, while both group had better performances than the removal group （48.3%±5.5, 22.7%±4.3） and the control group with the differences reaching the significant level （P〈0.05）. [Conclusion] The study provided technical support for the production of dairy cows and beef cattle.

Synthesis,Crystal Structure and in vitro Anticancer Studies of 1,2-Bis-benzimidazole-phenyl Copper(Ⅱ) Complex

One new benzimidazole derivative copper（II） complex 1（C10H6Cu N2, Mr = 217.71） has been synthesized and characterized by FT-IR and X-ray single-crystal diffraction. It crystallizes in orthorhombic, space group Pbcn with a = 17.417（2）, b = 8.9963（8）, c = 11.3432（9） ？, V = 1777.3（3） ？3, Z = 8, μ（Mo Kα） = 2.403, F（000） = 872, Dc = 1.627 g/cm3. The final R = 0.0598 for 1153 observed reflections with I 〉 2σ（I） and w R = 0.17 for all data. The in vitro anti-cancer activities of 1, Cu Cl2 and the benzimidazole ligand L were investigated using human cervical（Hela） and hepatocellular carcinoma（Hep-G2） cancer cell lines. The copper（II） complex can greatly inhibit the cell proliferation and show stronger cytotoxic activities against the tested cancer cell lines than both the ligand and copper（II） salt.

Reproductive Outcomes in Women with Prior Cesarean Section Undergoing In Vitro Fertilization:A Retrospective Case-control Study

The impact of prior cesarean section（CS） on the pregnancy and neonatal outcomes of in vitro fertilization and embryo transfer（IVF-ET） was investigated. A retrospective analysis was performed on 144 patients with prior CS between January 2013 and December 2015. The pregnancy, delivery, and neonatal outcomes of patients who had previous CS delivery and received IVF-ET were analyzed. The control group comprised 166 patients who had only previous vaginal delivery（VD） and received IVF-ET during the same period. The results showed that the basal follicle stimulating hormone level, estradiol level on human chorionic gonadotropin（h CG） day, gonadotrophin dosage, duration of stimulation, retrieved oocytes, fertilization rate, high-quality embryo rate, multiple birth rate, abortion rate and ectopic pregnancy rate had no significant difference between the two groups（P〉0.05）. The pregnancy rate（40.28% vs. 54.22%） and implantation rate（24.01% vs. 34.67%） were significantly lower（P〈0.05）, and the ratio of embryo difficulty transfer（9/144 vs. 0/166） was significantly higher in CS group than in VD group. The risk of pernicious placenta previa and postpartum hemorrhage in twin deliveries was significantly increased in CS group as compared with that in VD group（P〈0.05）, and gestational age and neonatal birth weight were significantly reduced in twin deliveries as compared with singleton deliveries in both groups（P〈0.05）. It was suggested that the existence of CS scar may impact embryo implantation and clinical pregnancy outcome, and increase the difficulty of ET. We should limit the number of transfer embryos to avoid multiple pregnancies and strengthen gestational supervision in patients with cesarean scar.

Intracytoplasmic sperm injection in cases with a history of in vitro fertilization failure

<abstract>Aim: To evaluate the effect of intracytoplasmic sperm injection (ICSI) in the management of cases with a history of conventional in vitro fertilization (IVF) failure. Methods: Two groups of patients, 19 with normal semen parameters and a history of IVF failure (metaphase Ⅱ oocytes: 0~30 %) and 28 with severe male factor infertility received ICSI technology during the same period. Ovarian stimulation was achieved by conventional procedure. Transvaginal ultrasound-guided oocyte collection was done 35~37 h after human chorionic gonadotrophin (hCG) injection. Only metaphase Ⅱ oocytes were selected for microinjection. Results: Fertilization was achieved with ICSI in all the patients. The fertilization rate (75.6 %±21.1 % vs. 73.9 %±19.2 %), cleavage rate (85.1 %±19.3 % vs. 82.7 %±22.1 %), clinical pregnancy rate per embryo transfer cycle (31.6 % vs. 28.6 %) and implantation rate per embryo (15.3 % vs. 14.4 %) did not differ significantly between the two groups. Conclusion: ICSI is a valuable method for couples with a history of IVF failure. These patients may have a similar ICSI result as in severe male infertility.

A highly homozygous and parthenogenetic human embryonic stem cell line derived from a one-pronuclear oocyte following in vitro fertilization procedure

Homozygous human embryonic stem cells （hESCs） are thought to be better cell sources for hESC banking because their human leukocyte antigen （HLA） haplotype would strongly increase the degree of matching for certain populations with relatively smaller cohorts of cell lines. Homozygous hESCs can be generated from parthenogenetic embryos, but only heterozygous hESCs have been established using the current strategy to artificially activate the oocyte without second polar body extrusion. Here we report the first successful derivation of a human homozygous ESC line （chHES- 32） from a one-pronuclear oocyte following routine in vitro fertilization treatment, chHES-32 cells express common markers and genes with normal hESCs. They have been propagated in an undifferentiated state for more than a year （〉P50） and have maintained a stable karyotype of 46, XX. When differentiated in vivo and in vitro, chHES-32 cells can form derivatives from all three embryonic germ layers. The almost undetectable expression of five paternally expressed imprinted genes and their HLA genotype identical to the oocyte donor indicated their parthenogenetic origin. Using genome-wide single-nucleotide polymorphism analysis and DNA fingerprinting, the homozygosity of chHES-32 cells was further confirmed. The results indicated that ‘ unwanted＇ one-pronuclear oocytes might be a potential source for human homozygous and parthenogenetic ESCs, and suggested an alternative strategyfor obtaining homozygous hESC lines from parthenogenetic haploid oocytes.

Untreated Prior Pulmonary Tuberculosis Adversely Affects Pregnancy Outcomes in Infertile Women Undergoing in vitro Fertilization and Embryo Transfer: A Large Retrospective Cohort Study

Objective Prior pulmonary tuberculosis(PTB) on chest X-ray(CXR) was commonly found in infertile patients receiving examinations before in vitro fertilization and embryo transfer(IVF-ET). It was unclear whether untreated PTB would affect pregnancy outcomes after IVF-ET.Method We conducted a retrospective cohort study of 14,254 infertile patients who had received IVFET at Peking University Third Hospital in 2017. Prior PTB was defined as the presence of signs suggestive of old or inactive PTB on CXR, with or without a clinical TB history. Patients who had prior PTB on CXR but had not received a clinical diagnosis and anti-TB therapy were included for analysis. Live birth,clinical pregnancy, and miscarriage rates were compared between the untreated PTB and non-PTB groups.Results The untreated PTB group had significantly lower clinical pregnancy(31.7% vs. 38.1%) and live birth(23.8% vs. 30.6%) rates than the non-PTB group(both P < 0.001). Multivariate analysis revealed that untreated PTB was a risk factor for decreased live birth rate [odds ratio(OR), 0.80;95% confidence interval(CI), 0.66–0.98;P = 0.028] in all patients and for increased miscarriage(OR, 4.19;95% CI,1.69–10.39;P = 0.002) and decreased live birth(OR, 0.45;95% CI, 0.24–0.83;P = 0.011) rates in patients with unexplained infertility.Conclusions Untreated PTB was associated with adverse pregnancy outcomes after IVF-ET, especially in patients with unexplained infertility, highlighting the clinical significance of PTB in this specific patient population.

Intramural pregnancy after in vitro fertilization and embryo transfer:A case report

BACKGROUND Intramural pregnancy is a rare type of ectopic pregnancy,which is diagnosed by transvaginal ultrasound and magnetic resonance imaging.Management strategies vary depending on the site of the pregnancy,the gestational age and the desire to maintain fertility.The incidence of intramural pregnancy in assisted reproductive technology is higher than that in natural pregnancy.CASE SUMMARY We present a case of intramural pregnancy after in vitro fertilization and elective single embryo transfer following salpingectomy.The patient was completely asymptomatic and her serumβ-human chorionic gonadotropin level increased from 290 m IU/m L to 1759 m IU/m L.Three-dimensional transvaginal ultrasound indicated a heterogeneous echogenic mass arising from the uterine fundus which was surrounded by myometrium and a slender and extremely hypoechoic area stretching to the uterine cavity which was thought to be a fistulous tract.Therefore,we considered a diagnosis of intramural pregnancy and laparoscopic surgery was conducted at 7 wk gestation.CONCLUSION Early diagnosis and treatment of intramural pregnancy is significant for maintaining fertility.

A nomogram predicting clinical pregnancy in the first fresh embryo transfer for women undergoing in vitro fertilization and intracytoplasmic sperm injection(IVF/ICSI) treatments

The extent to which factors affect the probability of clinical pregnancy in the first fresh embryo transfer after assisted conception is unknown.In order to examine the predictors of clinical pregnancy,a retrospective cohort study was launched between January 1,2013 and December 31,2016 in four infertility clinics including 19837 in vitro fertilization and intracytoplasmic sperm injection(IVF/ICSI)fresh cycles with known outcomes and relevant records.A multivariable logistic regression was used to select the most significant predictors in the final nomogram for predicting clinical pregnancy.Furthermore,the model was validated by an independent validation set and the performance of the model was evaluated by the receiver operating characteristic(ROC)curves along with the area under the ROC curve(AUC)and calibration plots.In a training set including 17854 participants,we identified that female age,tubal factor,number of embryos transferred,endometrial thickness and number of good-quality embryos were independent predictors for clinical pregnancy.We developed a nomogram using these five factors and the predictive ability was 0.66 for AUC(95%CI=0.64−0.68),which was independently validated in the validation set(AUC=0.66,95%CI=0.65−0.68).Our results show that some specific factors can be used to provide infertile couples with an accurate assessment of clinical pregnancy following assisted conception and facilitate to guide couples and clinicians.

Post-salpingectomy interstitial heterotopic pregnancy after in vitro fertilization and embryo transfer:A case report

BACKGROUND Heterotopic pregnancy(HP)refers to the coexistence of ectopic pregnancy and intrauterine pregnancy.Salpingectomy is proposed as a pretreatment before in vitro fertilization and embryo transfer(IVF-ET)to reduce the risk of HP.HP after IVF-ET occurs in women who had already underwent bilateral salpingectomy,even though it is extremely rare.CASE SUMMARY A case of a 29-year-old woman with recurrent interstitial HP after IVF-ET following salpingectomy is presented.The main symptom was a sudden and worsening pelvic pain.Physical examinations revealed signs of peritoneal bleeding and irritation with stable vital signs.Transvaginal ultrasound showed a live intrauterine pregnancy and another live embryo with cardiac activity in the left cornu extending beyond the lateral edge of the uterus.Her hemoglobin concentration was 8.0 g/dL,and serum human chorionic gonadotropin value was 171116.9 mIU/mL.With the diagnosis of ruptured HP with internal bleeding,an emergency laparoscopic resection of left cornu was performed.The interstitial pregnancy was removed with caution to protect the intrauterine pregnancy.After the surgical treatment,the intrauterine pregnancy continued with no complications.A healthy baby was delivered by caesarean section at 39 wk.Outcomes of another three cases are further summarized.CONCLUSION Post-salpingectomy HP is a rare but challenging condition.Surgical treatment is preferred in the case with a viable intrauterine pregnancy.

Effects of Ovarian Preservation Time on in vitro Maturation and in vitro Fertilization of Oocytes from Slaughtered Sheep

[Objectives] The aim was to study the effects of ovarian preservation time on in vitro fertilization of oocytes from slaughtered sheep. [Methods] The collected ovaries were randomly and evenly divided into four groups. They were preserved in physiological saline containing penicillin（ 100 IU/ml） and streptomycin（ 100 μg/ml） at 15-20 ℃ for 0（ Control）,6,12 and 18 h,respectively. Then,the oocytes were subjected to in vitro fertilization. [Results]The maturation rates,cleavage rates and blastocyst rates of the oocytes preserved for 6 and 12 h showed no significant differences compared with those of the oocytes preserved for0 h（ 72. 03%,70. 87% vs. 73. 68%; 74. 12%,72. 60% vs. 74. 49%; 22. 22%,20. 75% vs. 23. 29%）（ P 〉 0. 05）. There were also no significant differences in maturation rate,cleavage rate or blastocyst rate between the oocytes preserved for 18 and 0 h（ P 〉 0. 05）. [Conclusions] Within a certain rage（ 0-18 h）,storage time of ovary at 15-20 ℃ does not affect the continued development of oocytes from slaughtered sheep.

Cumulative live birth rates of in vitro fertilization/intracytoplasmic sperm injection after multiple complete cycles in China

There were few studies of cumulative live birth rates(CLBRs) based on multicenter reproductive clinical data from the general Chinese population.Here we report a retrospective cohort study,including 14 311 women with17 315 cycles,in three reproductive centers to evaluate two estimated parameters of CLBRs with multiple transfer cycles of in vitro fertilization(IVF)/intracytoplasmic sperm injection(ICSI) in a Chinese population.We found that CLBRs were related to female age and endometrial thickness.By the fourth transfer cycle,the conservative and optimal estimates of CLBRs were 52.95% and 77.30% in women under 30 years of age,and 18.17% and26.51% in those 37 years of age or older,respectively.The two estimates were 44.70% and 63.15% in women with endometrial thickness more than 7 mm,and 32.05% and 46.18% in those with less than 7 mm,respectively.In addition,body mass index(BMI),duration of infertility,and infertility diagnoses may also be related to CLBRs on certain conditions.The findings from this study on CLBRs after multiple transfer cycles of IVF/ICSI treatment on different conditions in the Chinese population should be beneficial to both infertile couples and clinicians.

Comparison between in vitro fertilization outcome of two motile sperm separation methods

Objective: To evaluate the efficiency of Percoll density gradient and swim-up methods for motile sperm isolation for in vitro fertilization and embryo transfer (IVF-ET) program. Methods: The fertilization rate, cleavage rate, embryo developing status and pregnancy outcome of 362 IVF cycles using sperm obtained by the two methods were studied. Results: There was no significant difference in fertilization rate and cleavage rate between the Percoll and swim-up groups. Although the two groups showed no significant difference in the embryo cell number, the percentage of embryos with<20% debris was significantly higher in the Percoll group (77.6%) than in swim-up group (65.9%). The pregnancy rate and the life birth rate were also significantly higher (P<0.01) in the Percoll group (43.7% and 70.3%, respectively) than in the swim-up group (36.6 % and 60.7 %, respectively). Conclusion: The efficiency of the Percoll density gradient method is superior to the swim-up method in motile sperm separation for the IVF-ET program. [Reprod Contracep (in Chinese) 2002; 22: 292]

Effects of difructose dianhydride (DFA)-Ⅳ on in vitro fertilization in pigs

Difructose dianhydride Ⅳ(DFA-Ⅳ) is produced from levan, which is a natural polysaccharide that belongs to the fructan family, through the activity of levan fructotransferase(LF) derived from microorganisms. Recently, DFA-Ⅳ has been expected to have diverse applications in the food and medical industry. Here, we examined the potential application of DFA-Ⅳ for in vitro fertilization(ⅣF) in pigs. In the assessment of acrosomal integrity during incubation, intact acrosomal or viable spermatozoa were highly sustained in 0.1% or 0.25% DFA-Ⅳ(69.8%-70.8%,P<0.05). Reactive oxygen species(ROS) levels during sperm incubation decreased following the addition of DFA-Ⅳ, and 0.1 %-0.5% DFA-Ⅳ in particular significantly decreased ROS production relative to that seen with no addition or 0.75% DFA-Ⅳ. Total fertilization(mono + polyspermic oocyte) rate was significantly higher in the addition of0.1% DFA-Ⅳ(94.2%) than with other concentrations(71.8%-86.7%, P<0.05). When using reduced ⅣF times and lower sperm numbers, we found that addition of 0.1%-0.5% DFA-Ⅳ significantly increased the fertilization rate(P<0.05). Fertilized oocytes treated with 0.1% DFA-Ⅳ exhibited higher embryonic development and blastocyst formation than those treated with other concentrations(P<0.05). Consequently, the addition of DFA-Ⅳ during ⅣF improved fertilization and embryonic development, suggesting the possible use of novel sugars for enhancement of assisted reproductive technology(ART) in mammals.

Effects of Different Culture Systems on In Vitro Fertilization of Oocyte in Bovine

[ Objective] To investigate the optimal culture system for in vitro fertilization （IVF） of oocyte in bovine. [ Method] The IVF of mature bovine oocytes was conducted and the fertilized eggs were cultured in vitro with different culture systems. In the traditional culture system, the TALP medium and BO medium were used as fertilization medium, respectively; and M-199 medium supplemented with 5% FCS was used as fertilized egg culture medium. In the transitional culture system, the TALP medium and BO medium were used as fertilization medium; 60% TALP and 40% M-199 supplemented with 5% FCS and 60% BO and 40% M-199 supplemented with 5% FCS were used as fertilized egg culture medium, respectively. The effects of different culture systems on fertilization rate and cleavage rate were observed. E Result] In the transitional culture system （with TALP medium as fertilization medium and with 60% TALP and 40% M-199 supplemented with 5% FCS as fertilized egg culture medium）, the fertilization rate and cleavage rate were increased to 77.8% and 55.6%, respectively. [ Conclusion] The transitional culture system （with TALP medium as fertilization medium and with 60% TALP and 40% M-199 supplemented with 5% FCS as fertilized egg culture medium） is the optimal culture system for IVF of bovine oocyte.