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]

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.

Effect of Tillage Methods and Foliar Fertilization (<i>Boost Extra</i>^TM) on Soil Physical Properties, Weed Dry Matter and Grain Yield of Sorghum in Ejiba, Kogi State, Nigeria

An experiment was carried out for two consecutive growing seasons (2012 and 2013) at the Research Site of the Lower Niger River Basin Development Authority, Ejiba, Nigeria, to examine the response of sorghum to tillage methods and foliar fertilizer (Boost ExtraTM) application. A split plot experiment was laid out in a Randomized Complete Block Design (RCBD) with three replicates to randomize the tillage methods (main plots) and foliar fertilizer application (sub-plots), respectively. The experiment comprised of three tillage methods: No Tillage (NT), Manual Tillage (MT) and convectional tillage (Ploughing, Harrowing and Ridging, PHR) and three foliar fertilizer rates: 0, 2 and 4 liters of foliar fertilizer per hectare. The parameters taken on soil physical properties and weed characters are soil moisture content (%), soil temperature (℃), weed species and weed dry weight (g). Growth and yield parameters taken are: average plant height (cm), stem girth (cm), leaf area (m2), days to 50% flowering, root dry weight (g), shoot dry weight (g), weight of 1000 seeds and grain yield per land area. Weeds were identified and harvested, and their dry weights were taken and recorded. Data were also collected from ten randomly selected plants in each plot. The data were statistically analyzed using GENSTAT. The analysis of variance (ANOVA) was carried out to find out the significance of variation among the treatments while the significant differences between mean treatments were separated using Duncan’s Multiple Range Test (DMRT) at 5% level of probability. The results obtained from this study indicated that tillage methods and foliar fertilizer application significantly affected growth and yield parameters of sorghum, consequently the yield per unit area. The results also indicated that “Manually Tilled” seedbed (MT) improved soil physical properties better than either plots with PHR or No Till plots in the study area. Foliar fertilizer application at 2 l/ha performed best in terms of growth and yield. It is therefore recommended that manual tillage should be used as a method of seedbed preparation for sorghum production. However, better and stable grain yield of sorghum could be obtained with the practice of manual tillage (MT) in combination with foliar fertilization at rate of 2 litres/ha. It is recommended that different tillage methods should be combined with foliar fertilizer application for higher grain yield in the study area.

Clinical study of different fertilization methods of assisted reproductive technology on neonatal birth defects

Objective:To investigate the incidence of neonatal birth defects in assisted reproductive technology(ART)by in vitro fertilization(IVF)and intracytoplasmic sperm injection(ICSI).Methods:The clinical data of 4229 cases of singleton deliver by infertile patients under 35 years old who received IVF/ICSI-ET in our center were analyzed.According to different fertilization methods,they were divided into IVF group(2967 cases)and ICSI group(1262 cases).The general situation of birth,birth defects and the location of defects were compared between the two groups.Results:a total of 38 cases of neonatal birth defects were found,the incidence of birth defects was 0.89%,including 30 cases(1.01%)in IVF group and 8 cases(0.64%)in ICSI group.There was no significant difference in the incidence of birth defects between the two groups(P>0.05).There was also no significant difference in birth weight,gestational age and gender ratio between the two groups(P>0.05).Conclusion:Different fertilization methods in assisted reproductive technology do not increase the incidence of neonatal birth defects.

Effects of Sulfur Fertilizer Application Methods on Grain Protein Content During Filling Stage of Winter Wheat

[ Objective] The experiment aimed to provide a theoretical base of optimal cultivation management for the high yield and good quality and high efficiency of winter wheat. [ Method] The effects of two sulfur fertilizer application methods on dynamic changes of grain protein content and glutenin content of Yumai 49 and Yumai 66 during wheat grain filling stage were studied under the field conditions. [Result] Both the grain protein and glutenin content of two cultivars were increased by sulfur fertilizer, particularly, the effects on Yumai 49 were more significant.[ Conclusion] The grain content and glutenin content of different wheat cultivars could be increased by taking different sulfur fertilizer application methods.

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.

In Vitro Fertilization of Angiosperms-10-Year Effort in China

This review gives a brief retrospect to the development on in vitro fertilization (IVF) of angiosperms in China. During the last decade Chinese scientists put great enthusiasm and efforts on IVF system construction and built up notable contributions to the flourish of this field. Keeping pace with international development and participating international cooperation in the field of IVF, Chinese scientists have now focused on the investigation of basic mechanism relevant to possible gamete interaction, egg cell activation and early embryogenesis by IVF. In vitro manipulation techniques are combined with cytological and molecular biological approaches to unveil the double fertilization mysteries.

In Vitro Fertilization in Maize and Tobacco: The Fusion Patterns During Sexual Cell Fusion

Large scale of sexual cell fusion was carried out in order to observe the fusion pattern during in vitro fertilization with special interest in the influence of cell volume on the membrane behavior. Three patterns could be recognized in sexual cell fusion, which was supported by fluorescent microscopy with the aid of video enhanced system and cooled CCD. It was found that the fusion pattern and cell membrane behavior were related to the cell volume ratio of two fusing cells. The results reported here might be useful for interpreting and evaluating data from in vitro fertilization experiments and for explaining male cytoplasm exclusion during fertilization.

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.

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.

Does Lower Dose of Long-acting Triptorelin Maintain Pituitary Suppression and Produce Good Live Birth Rate in Long Down-regulation Protocol for In-vitro Fertilization?

The effects of pituitary suppression with one-third depot of long-acting gonadotropin-releasing hormone（Gn RH） agonist in Gn RH agonist long protocol for in vitro fertilization（IVF）/intracytoplasmic sperm injection（ICSI） were investigated. A retrospective cohort study was performed on 3186 cycles undergoing IVF/ICSI with Gn RH agonist long protocol in a university-affiliated infertility center. The pituitary was suppressed with depot triptorelin of 1.25 mg or 1.875 mg. There was no significant difference in live birth rate between 1.25 mg triptorelin group and 1.875 mg triptorelin group（41.2% vs. 43.7%）. The mean luteinizing hormone（LH） level on follicle-stimulating hormone（FSH） starting day was significantly higher in 1.25 mg triptorelin group. The mean LH level on the day of human chorionic gonadotrophin（h CG） administration was slightly but statistically higher in 1.25 mg triptorelin group. There was no significant difference in the total FSH dose between the two groups. The number of retrieved oocytes was slightly but statistically less in 1.25 mg triptorelin group than in 1.875 mg triptorelin group（12.90±5.82 vs. 13.52±6.97）. There was no significant difference in clinical pregnancy rate between the two groups（50.5% vs. 54.5%）. It was suggested that one-third depot triptorelin can achieve satisfactory pituitary suppression and produce good live birth rates in a long protocol for IVF/ICSI.

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.

In Vitro Fertilization Outcomes Following Assisted Hatching of Embryos with Thick Zona Pellucida—A Prospective Randomized Study

Purpose: Impaired hatching is associated with implantation failure following in vitro fertilization (IVF). Thickening or hardening of the zona pellucida (ZP) has been proposed as a factor in this impairment. We examined whether selective assisted hatching (AH) is beneficial with embryos having a thick ZP. Methods: This prospective, randomized controlled study was performed in the IVF unit of an obstetrics and gynecology department in a university-affiliated hospital. Only patients undergoing IVF and having a ZP thickness of ≥17 μm measured in all their embryos were included. In the intervention group, AH was applied to all embryos, before their transfer. In the control group, embryos were transferred without AH. Implantation, clinical pregnancy and live birth rates were the study endpoints. Results: Both study arms were comparable in most baseline parameters. The two groups did not differ in implantation rates (14.1% control vs. 8.92% intervention, odds ratio (OR) = 0.5974, 95% confidence interval (CI) 0.325 - 1.1), clinical pregnancy rates (36.7% vs. 25.8%, OR = 0.6025, 95% CI 0.274 - 1.325), or live birth rates (25% vs. 18.9%, OR = 0.7021, 95% CI 0.291 - 1.691). Conclusions: Selecting embryos for AH by their ZP thickness as a sole parameter was not found to be beneficial and to improve IVF outcome.

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.