Embryo Implantation Rate Research Articles

P-130 Progesterone-primed cycles result in slower embryos without compromising the implantation potential, with the advantage of oral administration and potential cost reduction: A time-lapse imaging study

Abstract Study question Could exogenous progestin replace the use of an antagonist of GnRH (GNRH-antagonist) without any effects on embryo morphokinetics and implantation rate in freeze-all cycles? Summary answer Exogenous progestin leads to slower embryo development and increased cyclés cancellation rate, with increased implantation rate when compared to cycles using an GnRH-antagonist. What is known already Improvements in cryopreservation techniques associated with the expansion of elective-single embryo transfer have steadily increased the use of deferred embryo transfers. This gives the opportunity to break away from the standard sequence of stimulation–retrieval–transfer, and to consider new strategies for pharmacological control of follicle growth. Usual ovarian stimulation regimens use an analog of the GnRH to prevent the LH surge and premature ovulation. Since progesterone is able to block the LH surge question remains on whether exogenous progesterone may replace the use of an GnRH analogue without compromising embryo development, in cycles followed by embryo cryopreservation. Study design, size, duration This cohort study, performed in a private university-affiliated IVF center, from Mar/2019 - Mar/2021, included 288 freeze-all ICSI cycles and its 2,768 respective embryos. Patients were age matched, according to the age, into groups depending on the protocol used to prevent the LH surge: Progestin-Primed-Group (n = 144 cycles and 1,360 embryos) and GnRH-Antagonist-Group (n = 144 cycles and 1,408 embryos). Embryos were cultured in a time-lapse imaging incubation system (TLI) and embryo morphokinetics were compared among the groups Participants/materials, setting, methods Evaluated kinetic markers were timing to pronuclei appearance (tPNa) and fading (tPNf), to two, three, four, five, six, seven, and eight cells (t2 - t8), to morulation (tM), start of blastulation (tSB) and blastulation (tB). Durations of the second (t3-t2) and third (t5-t3) cell cycles (cc2 and cc3) and timing to complete synchronous divisions s1 (t2-tPNf), s2 (t4-t3), and s3 (t8-t5) were also calculated. The KID-Score ranking, laboratorial and clinical outcomes were also evaluated. Main results and the role of chance Mean maternal and paternal ages were 37.0 ± 3.8 and 39.0 ± 6.4 years old. Slower tPNa (6.2 ± 0.2 vs. 7.0 ± 0.2, p = 0.008), t2 (27.2 ± 0.3 vs. 26.2 ± 0.3, p = 0.045), t7 (56.4 ± vs. 54.7 ± 0.5, p = 0.046), tM (89.3 ± 0.8 vs. 87.1 ± 0.6, p = 0.045), tSB (101.5 ± 0.8 vs. 110.8 ± 0.1, p = 0.012), tB (111.0 ± 0.8 vs. 108.5 ± 0.7, p = 0.034), were observed among embryos derived from Progestin-Primed cycles. Similar tPNf, t3, t4, t5, t6, t8, timing to cc2, cc3, s1, s2, and s3 were observed among the groups. No significant differences were noted in the Kid-score D5, number of aspirated follicles, retrieved oocytes, oocyte yield, mature oocytes, and rates of mature oocytes, fertilization, and blastocyst formation. The cyclés cancelation (15.7% vs. 2.0%, p = 0.004) and implantation rates (63.1% ± 6.1 vs. 44.4% ± 6.3, p = 0.004) were increased in the Progestin-Primed-Group, however no significant differences were noted in the cumulative pregnancy (64.4% vs. 49.0%, p = 0.104) and miscarriage rate (2.6% vs. 8.6%, p = 0.554) for Progestin-Primed and GnRH-Antagonist groups, respectively. The expense for the ovulation prevention using the GnRH-Antagonist was U$318.18, while by using progestins U$ 11.05 was sufficient to inhibit the premature LH surge. Limitations, reasons for caution This study has limitations, such as the retrospective design and small sample size. Wider implications of the findings Despite the increased implantation rate and potential cost reduction, the high cancellation rate and slower embryo development in the progestin-protocol cannot be ignored. Delayed embryo transfer due to the freeze-only approach may also be inconvenient. Before considering any protocols for LH surge prevention, pros and cons must be carefully evaluated. Trial registration number N/A

Functionalized human umbilical cord mesenchymal stem cells and injectable HA/Gel hydrogel synergy in endometrial repair and fertility recovery

Intrauterine adhesions (IUA) caused by endometrial injury are one of the main causes of female infertility. The current treatments for endometrial injury offer limited clinical benefits and cannot improve endometrial receptivity and pregnancy outcomes. Tissue engineering and regenerative medicine are considered potential solutions to address this concern and may offer effective treatment methods for the regeneration of injured human endometrium. Herein, we prepared an injectable hydrogel based on oxidized hyaluronic acid (HA-CHO) and hydrazide-grafted gelatin (Gel-ADH). The injectable hydrogel showed satisfactory biocompatibility when mixed with human umbilical cord mesenchymal stem cells (hUCMSCs). In an endometrial injury rat model, the treatment with hUCMSCs-loaded injectable hydrogel significantly enhanced the thickness of the endometrium and increased the abundance of blood vessels and glands in the injured endometrium compared to the control group. The hUCMSCs-loaded injectable hydrogel treatment significantly reduced endometrial fibrosis, decreased the expression of the pro-inflammatory factors (IL-1β and IL-6) and increased the expression of the anti-inflammatory factor (IL-10). This treatment induced endometrial VEGF expression by activating the MEK/ERK1/2 signaling pathway. Moreover, this treatment improved endometrial receptivity to the embryo and restored the embryo implantation rate similar to the sham group (48% in the sham group vs 46% in the treatment group), and this treatment achieved pregnancy and live birth in rats with endometrial injury. In addition, we also preliminarily validated the safety of this treatment in the maternal rats and fetuses. Collectively, our study showed that the hUCMSCs-loaded injectable hydrogel hold potential as an effective treatment strategy promoting rapid recovery of endometrial injury, and this hydrogel is a promising biomaterial for regenerative medicine applications. Statement of significance1. Oxidized hyaluronic acid (HA-CHO)/hydrazide-grafted gelatin (Gel-ADH) hydrogel combined with human umbilical cord mesenchymal stem cells (hUCMSCs) are effective in improving the regeneration of endometrium in the endometrial injury rat model.2. The hUCMSCs-loaded hydrogel treatment promotes the expression of endometrial VEGF through MEK/ERK1/2 signaling pathway and regulates the balance of inflammatory factors.3. The embryo implantation and live birth rates restore to normal level in the endometrial injury rat model, and the hydrogel has no adverse effects on maternal rats, fetuses, and offspring development after the treatments.

Adding a ketogenic dietary intervention to IVF treatment in patients with polycystic ovary syndrome improves implantation and pregnancy

Patients with polycystic ovary syndrome (PCOS) on a high-carbohydrate diet intrinsically suffer from exacerbated glucotoxicity, insulin resistance (IR), and infertility. Lowering the carbohydrate content has improved fertility in patients with IR and PCOS; however, the effects of a well-controlled ketogenic diet on IR and fertility in PCOS patients undergoing in vitro fertilization (IVF) have not been reported. Twelve PCOS patients with a previous failed IVF cycle and positive for IR (HOMA1-IR>1.96) were retrospectively evaluated. Patients followed a ketogenic diet (50 g of total carbohydrates/1800 calories/day). Ketosis was considered when urinary concentrations were > 40 mg/dL. Once ketosis was achieved, and IR diminished, patients underwent another IVF cycle. The nutritional intervention lasted for 14 ± 11 weeks. Carbohydrate consumption decreased from 208 ± 50.5 g/day to 41.71 ± 10.1 g/day, which resulted in significant weight loss (−7.9 ± 1.1 kg). Urine ketones appeared in most patients within 13.4 ± 8.1 days. In addition, there was a decrease in fasting glucose (−11.4 ± 3.5 mg/dl), triglycerides (−43.8 ± 11.6 mg/dl), fasting insulin (−11.6 ± 3.7 mIU/mL), and HOMA-IR (−3.28 ± 1.27). All patients underwent ovarian stimulation, and compared to the previous cycle, there was no difference in oocyte number, fertilization rate, and viable embryos produced. However, there was a significant improvement in the implantation (83.3 vs. 8.3 %), clinical pregnancy (66.7 vs. 0 %), and ongoing pregnancy/live birth rates (66.7 vs. 0 %). Here, restriction in carbohydrate consumption in PCOS patients induced ketosis, improved key metabolic parameters, and decreased IR. Even though this did not affect oocyte or embryo quality or quantity, the subsequent IVF cycle significantly improved embryo implantation and pregnancy rates.

The transcriptional foundations of interferon-λ-mediated endometrial cell to uterine receptivity.

Interferon-λ (IFN-λ) is a novel non-redundant regulator that participates in the fetal-maternal immune interaction, including immune regulation, uterine receptivity, cell migration and adhesion, and endometrium apoptosis. However, the exact transcriptional foundation for endometrial signaling of IFN-λ is not completely understood, and studies regarding IFN-λ to implantation failure in vivo are limited. The gene expression profile of human endometrial Ishikawa cell line treated with IFN-λ or IFN-α (100ng/mL) for 6h was analyzed using RNA-sequencing. Real-time qPCR, western blotting, and enzyme-linked immunosorbent assay (ELISA) tests were used to validate these sequencing data. An in vivo IFN-λ knock-down mouse pregnancy model was performed, and the phenotype analysis and the intrauterine biomarkers detection were applied with the uterus samples. High levels of messenger RNA (mRNA) were detected for genes previously associated with endometrial receptivity, including LIF, AXL, CRYAB, EPHB2, CCL5, and DDX58, following IFN-λ treatment. Moreover, the data indicated IFN-λ reduced pro-inflammatory gene activity compared with IFN-α, including members of the ISG, TNF, SP100 and interleukin genes. The in vivo mouse pregnancy model showed that inhibition of intrauterine IFN-λ results in aberrant epithelial phenotype and significantly decreases the embryo implantation rates and derails normal uterine receptivity. These findings demonstrate the antagonistic and agonistic roles of IFNs in the endometrial cell, suggesting a selective role of IFN-λ in endometrial receptivity and immunological tolerance regulation. Moreover, the findings provide valuable insight into potential biomarkers related to endometrial receptivity and facilitate an understanding of the molecular changes observed during infertility treatment and contraception usage.

Effect of low-molecular-weight heparin in women undergoing frozen-thawed embryo transfer cycles: a retrospective cohort study

BackgroundRecurrent pregnancy loss (RPL) and recurrent implantation failure (RIF) during in vitro fertilization (IVF) treatment are still tough problems without effective treatments; thus, they are important research topics. There is controversy on whether low molecular weight heparin (LMWH) improves pregnancy outcomes in women with unexplained RPL and RIF. Moreover, currently, there is a paucity of reports on the role of LMWH in the entire population undergoing frozen-thawed embryo transfer (FET) cycles. This study aimed to estimate the effects of LMWH on pregnancy outcomes in women undergoing FET cycles.MethodsThere were 1881 female patients included in the study. Of the 1881 patients, 107 underwent preimplantation genetic diagnosis cycles, which were analyzed individually. The patients were divided into two groups: the LMWH group received injections of 4100 IU/d LMWH from the day of transfer until 14 ± 2 days posttransplant, the control group was the comparison group (without LMWH use). The baseline characteristics and reproductive outcomes of the patients were reviewed.ResultsOf the 1774 women with normal FET cycles, no significant differences were found in the number of embryos implanted (1.31 ± 0.02 vs. 1.28 ± 0.02), embryo implantation rate, biochemical pregnancy rate, clinical pregnancy rate, live birth rate, late abortion rate, and ectopic pregnancy rate between the two groups. The LMWH group had a higher early abortion (17.8% [76/427] vs. 12.5% [55/439], p = 0.030). In the sub-group analysis, among the patients who underwent more than four transfers, the LMWH group had a lower late abortion rate (1.7% [1/60] vs. 13.2% [7/53], p = 0.043). Similarly, of the 107 women who underwent preimplantation genetic diagnosis cycles, the reproductive outcomes were comparable between the two groups.ConclusionIn the general population and PGD patients, LMWH did not improve pregnancy outcomes. Therefore, the routine use of LMWH is not recommended for early treatment.

Women undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) might benefit from maintaining serum luteinizing hormone levels: A retrospective analysis.

We aimed to evaluate the effect of serum luteinizing hormone (LH) levels on human chorionic gonadotropin (HCG) injection day (LHHCG) on outcomes of in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) patients. It is a retrospective cohort study involving 620 women who had an IVF cycle in Taizhou Hospital Affiliated to Wenzhou Medical University between 2018-2020. The participants were divided into different groups according to LHHCG level and age. The clinical data and outcomes were compared between groups. The numbers of follicles (≥ 14 mm) on HCG day, retrieved oocytes, mature oocytes, and two pronuclei (2PN) embryos in women with LHHCG < 2 IU/L were more than those with LHHCG ≥ 2 IU/L. Women with LHHCG < 2 IU/L had lower high-quality embryo rate (42.2% vs. 46.5%, p = 0.002) and implantation rate (40.0% vs. 58.8%, p = 0.044) compared to those with LHHCG ≥ 2 IU/L. When LHHCG < 2 IU/L, there was no significant difference in implantation rates in patients < 35 years compared to those ≥ 35 years. When LHHCG ≥ 2 IU/L, patients < 35 years old had higher implantation rates (71.7% vs. 41.2%, p < 0.001) compared to those ≥ 35 years old. The success rates of IVF fertilization and ICSI fertilization and biochemical and clinical pregnancy rates were not significantly different between groups. Our results demonstrated that women undergoing IVF/ICSI-ET might benefit from maintaining LHHCG levels at ≥ 2 IU/L. In addition, age might associate with LHHCG levels and be a better determining factor of the transfer outcome than serum LHHCG levels for IVF/ICSI-ET.

Comparison of Pregnancy Outcomes in Thyroid Antibody-Positive Women with Different Fertilization Methods

<i>Objective</i> To compare the pregnancy outcomes of thyroid antibody (ATA) positive women treated by different fertilization methods during in vitro fertilization-embryo transfer. Methods A total of 204 female patients with normal thyroid function and positive ATA in the reproductive Medicine Center of the First Hospital of Shanxi Medical University from January 2020 to January 2022 were selected. According to different fertilization methods, they were divided into IVF group and ICSI group, including 115 IVF cycles and 89 ICSI cycles. The general data, clinical indicators after ovulation induction, fertilization, embryo status, and pregnancy outcome of the two groups were compared. <i>Results</i> There were no significant differences in age, BMI, bE₂, FSH, FT₃, FT₄, AFC, Gn dosage, Gn stimulation time, E₂ on HCG day, P on HCG day, intrauterine thickness on HCG day, number of retrieved oocytes and average number of embryos transferred between the two groups (P>0.05). The fertilization rate of the ICSI group was higher than that of IVF group within the group, while the high-quality embryo rate was significantly lower than that of the IVF group, with statistical significance (P<0.05). There were significant differences in sperm motility and sperm density between the two groups (P<0.05), and there was no significant difference between sperm volume and normal morphology rate (P>0.05). There were no significant differences in embryo implantation rate, biochemical pregnancy rate, clinical pregnancy rate, early abortion rate and live birth rate between the two groups (P>0.05). Logistic regression analysis showed that the method of assisted pregnancy and semen quality were not independent factors affecting high-quality embryo (P>0.05). In IVF group, TGAb was negatively correlated with fertilization rate (r=-0.202, P<0.05); and in ICSI group, TPOAb was negatively correlated with high quality embryo rate (r=-0.349, P<0.05). <i>Conclusion</i> Thyroid autoimmunity (TAI) in infertile women undergoing assisted reproductive technology (ART), the semen quality should be considered as the priority criteria for ATA. ICSI should not be recommended as routine fertilization.

Comparison of uterine, endometrial and subendometrial blood flows in predicting pregnancy outcomes between fresh and frozen-thawed embryo transfer after GnRH antagonist protocol: a retrospective cohort study

This retrospective cohort study aimed to compare endometrial receptivity and pregnancy rate between fresh embryo transfer (ET) and frozen-thawed ET after gonadotrophin-releasing hormone (GnRH) antagonist protocol in normal ovarian responders. The patients were divided into two groups: the fresh ET group and the frozen-thawed ET group. Uterine artery resistance index (RI) and endometrial thickness were lower in the frozen-thawed ET group. The proportion of detectable endometrial–subendometrial flow was significantly higher in the frozen-thawed ET group. There was no significant difference in miscarriage rate between the two groups. Frozen-thawed ET group had a significantly higher CPR (56.0% vs. 48.1%), implantation rate (32.2% vs. 26.4%), and LBR (45.4% vs. 36.5%) than the fresh ET group. In GnRH antagonist protocol, elective frozen-thawed ET should be ideally taken, as this could improve embryo implantation rate, clinical pregnancy rate, and live birth rate, thus presenting an effective strategy to enhance the embryo utilization rate. IMPACT STATEMENT What is already known on this subject? The clinical pregnancy rate following fresh embryo transfer (ET) was lower than frozen-thawed ET after GnRH antagonist protocol. IVF success depends on embryo quality, embryo-endometrium interaction and endometrial receptivity. A good blood supply toward the endometrium is generally considered a requirement for implantation. What do the results of this study add? Uterine artery RI and endometrial thickness were significantly lower in the frozen-thawed ET group. The proportion of detectable endometrial–subendometrial flow was significantly higher in the frozen-thawed ET group. Frozen-thawed ET group had a significantly higher clinical pregnancy rate, implantation rate and live birth rate than the fresh ET group after GnRH antagonist protocol. What are the implications of these findings for clinical practice and/or further research? In GnRH antagonist protocol, elective frozen-thawed ET should be ideally taken, as this could improve embryo implantation rate, clinical pregnancy rate and live birth rate, thus presenting an effective strategy to enhance the embryo utilization rate.

Hormone replacement therapy alone or in combination with tamoxifen in women with thin endometrium undergoing frozen-thawed embryo transfer: A retrospective study.

To investigate the effects of two protocols (hormone replacement therapy (HRT) alone or in combination with tamoxifen) on the endometrium and pregnancy outcome of patients with thin endometrium in frozen-thawed embryo transfer (FET) cycles. A total of 465 infertile patients with thin endometrium who underwent FET between January 2020 to June 2021 at the Drum Tower Hospital affiliated with Nanjing University Medical School were retrospectively analyzed. A total of 187 patients were given tamoxifen in addition to HRT (TMXF-HRT group), whereas 278 patients were given only HRT (HRT group). Clinical data were compared between the two groups, including general characteristics, endometrial thickness, and clinical pregnancy outcomes. There were no significant differences in baseline characteristics of all enrolled patients between two groups. Serum progesterone (P) was higher in HRT group than in the TMXF-HRT group (0.28 ± 0.53 ng/mL vs. 0.15 ± 0.25 ng/mL, P = 0.002). There was a significant increase in endometrial thickness in the TMXF-HRT group compared with the HRT group (OR: 1.54, 95% CI: 1.32-1.75, P < 0.001). There were no significant differences in the clinical pregnancy rate, embryo implantation rate, early miscarriage rate, or live birth rate between these two groups. Although tamoxifen when used in combination with hormone replacement therapy can significantly increase endometrial thickness, it may not have a role in improving the pregnancy outcomes of patients with thin endometrium undergoing FET cycles.

The influence of preincubation time of prepared sperm before IVF on fertilization, embryo developmental competence and the reproductive outcomes.

It has been provided that if incubation time of prepared sperm can affect sperm motility and DNA fragment, but little is known about the influence of sperm preincubation time (SI) on the sperm's fertilizing ability, subsequent embryonic development and pregnancy outcomes in in vitro fertilization (IVF). The aim of this study was to explore the association of SI with fertilization rate, embryo development and clinical outcomes in IVF, further, to find an optimal preincubation time for prepared sperm before insemination in IVF. This retrospective cohort study included a total of 1453 infertile couples undergoing IVF in our center performed from January 2016 to January 2019. Sperm were preincubated at 37℃ 6% CO₂ for different times before insemination. Preincubation time associated with fertilization rate (FR), 2PN rate, D3 good quality embryo rate, fresh embryo implantation rate (IR), blastocyst formation rate, cumulative pregnancy rate (CPR), cumulative ongoing pregnancy rate (COPR), cumulative live birth rate (CLBR), newborn health and gender ratio were analyzed by chi-square analysis. FR and 2PN rate of SI more than four hours SI groups (> 4 h SI group) decreased significantly compared with other SI groups (p < 0.01). There were no significant differences of the D3 high quality embryo rate among five SI groups. The blastocyst formation rate of > 4 h SI group was significantly lower than that of 2-3 h SI group (45.5% vs 56.1%, p < 0.05); and 1-2 h SI group also had significant difference with 2-3 h and 3-4 h SI group (48.9% vs 56.1% and 54.6%, p < 0.05). There were a significant decrease of fresh IR and CPR in ≤1 h SI group compared with 1-2 h SI group (19.6% vs. 38.0%, p < 0.05; 62.7% vs 73.7%, p < 0.05); ≤ 1 h SI group also have the lowest CLBR (45.6%), it had statistic differences with 1-2 SI group and 3-4 SI group (45.6% vs 63.2%, p < 0.01; 45.6% vs 61.2%, p < 0.05). The sperm preincubated time at 37℃ 6% CO₂ before insemination could influence sperm fertilizing ability, blastocyst formation, embryo implantation and CLBR in IVF cycles. The best time for prepared sperm preincubation at 37℃ is one to four hours before insemination in IVF.

MicroRNAs as A Biomarker to Predict Embryo Quality Assessment in In Vitro Fertilization.

Embryo selection for in vitro fertilization (IVF) is an effort to increase the success rate of embryo implantation. Factors influencing the success of embryo implantation include embryo quality, endometrial receptivity, embryo characteristics, and maternal interactions. Some molecules have been found to influence these factors, but their regulatory mechanisms are unclear. MicroRNAs (miRNAs) are reported to play an essential role in the embryo implantation process. miRNAs are small non-coding RNAs consisting of only 20 nucleotides that play an essential role in the stability of gene expression regulation. Previous studies have reported that miRNAs have many roles and are released by cells into the extracellular environment for intracellular communication. In addition, miRNAs can provide information related to physiological and pathological conditions. These findings encourage research development in determining the quality of embryos in IVF to increase the implantation success rate. Moreover, miRNAs can provide an overview of embryo-maternal communication and potentially be noninvasive biological markers of embryo quality, which could increase assessment accuracy while reducing mechanical damage to the embryo itself. This review article summarizes the involvement of extracellular miRNAs and the potential applications of miRNAs in IVF.

Mst1-mediated phosphorylation of Nur77 improves the endometrial receptivity in human and mice.

Successful embryo implantation requires the attachment of a blastocyst to the receptive endometrial epithelium, which was disturbed in the women with recurrent implantation failure (RIF). Endometrial β3-integrin was the most important adhesion molecule contributing to endometrial receptivity in both humans and mice. Nur77 has been proven indispensable for fertility in mice, here we explore the role of Nur77 on embryo-epithelial adhesion and potential treatment to embryo implantation failure. The expression and location of Mst1 and Nur77 in endometrium from fertile women and RIF patients were examined by IHC, qRT-PCR and Western blotting. Invitro kinase assay following with LC-MS/MS were used to identify the phosphorylation site of Nur77 activated by Mst1. The phosphorylated Nur77 was detected by phos-tag SDS-PAGE assay and specific antibody against phospho-Nur77-Thr366. The effect of embryo-epithelium interaction was determined in the BeWo spheroid or mouse embryo adhesion assay, and delayed implantation mouse model. RNA-seq was used to explore the mechanism by which Nur77 derived peptide promotes endometrial receptivity. Endometrial Mammalian sterile 20 (STE20)-like kinase 1 (Mst1) expression level was decreased in the women with RIF than that in the fertile control group, while Mst1 activation in the epithelial cells promoted trophoblast-uterine epithelium adhesion. The effect of Nur77 mediated trophoblast-uterine epithelium adhesion was facilitated by active Mst1. Mechanistically, mst1 promotes the transcription activity of Nur77 by phosphorylating Nur77 at threonine 366 (T366), and consequently increased downstream target β3-integrin expression. Furthermore, a Nur77-derived peptide containing phosphorylated T366 markedly promoted mouse embryo attachment to Ishikawa cells ([4 (2-4)] vs [3 (2-4)]) and increased the embryo implantation rate (4 vs 1.4) in a delayed implantation mouse model by regulating integrin signalling. Finally, it is observed that the endometrial phospho-Nur77 (T366) level is decreased by 80% in the women with RIF. In addition to uncovering a potential regulatory mechanism of Mst1/Nur77/β3-integrin signal axis involved in the regulation of embryo-epithelium interaction, our finding provides a novel marker of endometrial receptivity and a potential therapeutic agent for embryo implantation failure. National Key Research and Development Program of China (2018YFC1004400), the National Natural Science Foundation of China (82171653, 82271698, 82030040, 81971387 and 30900727), and National Institutes of Health grants (R01HL103869).

The therapeutic effects and optimal timing of granulocyte colony stimulating factor intrauterine administration during IVF-ET

Most of embryos fail to produce live offspring during In Vitro Fertilization-Embryo Transfer (IVF-ET) procedure. There is a dearth of research activity addressing this problem despite the significant population of women suffering from repeated implantation failure after transfer of high-quality of embryos. As a clinically accessible option, granulocyte colony stimulating factor (G-CSF) is often used for the treatment to improve the rates of embryo implantation. However, there are currently no evidence-based standardized protocol for the clinical use of G-CSF. G-CSF was administered into one side of mouse uterine horns and saline was infused into the other side of horns as a control. Intrauterine G-CSF administration showed maximal effects 24 h after administration in enhancing endometrial receptivity and subsequent increase of angiogenesis by demonstrating elevated integrin β3 and OPN and reduced cytotoxicity of NK cells. Furthermore, G-CSF administration 24 h prior to embryo transfer promoted the stability of attached embryos at the early stage of implantation in vitro. Our findings suggest as new consensus criteria providing a potential therapeutic strategy of the clinical use of G-CSF to achieve maximal effects of IVF-ET for patients who are suffering from repeated implantation failure with the problems with endometrial receptivity.

Analysis of the effect of phloroglucinol on pregnancy outcomes involving frozen embryo transfers in patients with endometriosis: A retrospective case-control study.

Abnormal contraction of uterus and vascular smooth muscle lead to the formation of hypoxia environment in uterus. Abnormal contraction may be the basis of dysmenorrhea, endometriosis, infertility and other diseases. Phloroglucinol is a non-atropine and non-papaverine smooth muscle spasmolytic agent, which can reduce the abnormal contraction of uterine smooth muscle. This study investigated the effect of phloroglucinol on frozen embryo transfer in patients with endometriosis. The data of patients with endometriosis who underwent a frozen embryo transfer in Shanghai Changzheng Hospital from August 2018 to August 2021, comprising a total of 453 cycles, were retrospectively analyzed. The patients for whom phloroglucinol was included over 217 cycles were administered intramuscully 40 mg phloroglucinol starting on the day of progesterone administration, then once daily up to day 7 after the embryo transfer. Those for whom phloroglucinol was not administered over 236 cycles were used as the control group. The age of 35 years was used as a boundary in this study to observe the pregnancy outcomes of patients in the two different age groups. The biochemical pregnancy rate (63.13% vs. 51.27%), embryo implantation rate (44.64% vs. 33.60%), clinical pregnancy rate (59.64% vs. 48.30%), and live birth rate (52.99% vs. 36.86%) after the administration of phloroglucinol were higher than for patients in the control group, and the early abortion rate (7.75% vs. 20.18%) was also lower. The differences were statistically significant (P < 0.05). In particular, in the age group <35 years old, the embryo implantation rate (51.81% vs. 39.38%), clinical pregnancy rate (69.34% vs. 57.55%), and the live birth rate (63.50% vs. 44.60%) after phloroglucinol intervention rose significantly, and the abortion rate dropped (6.32% vs. 17.5%), indicating a statistically significant difference (P < 0.05). However, pregnancy outcomes showed no difference in the age group ≥35 years old (P > 0.05). Continuous low-dose phloroglucinol pretreatment before and after frozen embryo transfer can improve both the clinical pregnancy and live birth rates and reduce the risk of abortion in younger infertile patients with endometriosis.

Are testicular sperms superior to ejaculated sperms in couples with previous ART failure due to high rate of fragmented embryos? A retrospective cohort study.

The aim was to clarify whether using testicular sperm reduces embryo fragmentation and improves cycle outcomes. Fragmented embryo was defined as an embryo in which fragments account for more than one third of the embryonic surface area. High rate of fragmented embryos was defined by a proportion of fragmented embryos higher than 50%. We recruited infertile couples who had undergone at least one ovarian stimulation cycle using ejaculated sperm but failed to conceive due to high rate of fragmented embryos in each previous cycle. After fully informed consent, the couples agreed to obtain testicular sperm by testicular puncture and use testicular sperm for intracytoplasmic sperm injection (ICSI). The normal fertilization rate, transferable embryo rate, fragmented embryo rate and cycle outcomes were compared between ejaculated sperm group (EJA-sperm group) and testicular sperm group (TESTI-sperm group). Twenty-two couples who agreed to participate in our study underwent 32 ICSI cycles with ejaculated spermatozoa and 23 ICSI cycles with testicular spermatozoa. Embryo transfers were cancelled in 8 ejaculated cycles and 4 testicular cycles because of no transferable embryos. There were no significant differences in age, normal fertilization rate and high-quality embryo rate between ejaculated and testicular groups. The transferable embryo rate and implantation rate in TESTI-sperm group were significantly higher than those in EJA-sperm group (36.9% vs. 22.0%, p < 0.01; 34.2% vs. 0%, p < 0.001). The fragmented embryo rate in TESTI-sperm group was significantly lower than that in EJA-sperm group (61.2% vs. 75.7%, p < 0.05). Our small retrospective cohort study suggests that using testicular sperm may be a recommended option for couples with previous ART failure because of high rate of fragmented embryos. Large samples, multicenter studies or randomized controlled trial (RCT) are needed to further confirm the superiority of testicular sperm.

Effect of interval between oocyte retrieval and resuscitation embryo transfer on pregnancy outcomes.

Resuscitation transfer of embryos after elective cryopreservation has been widely applied in in vitro fertilization-embryo transfer (IVF-ET) therapy for human infertility or sterility owing to higher embryo implantation rates. This method separates oocyte retrieval from embryo transfer. The optimal time for frozen embryo transfer (FET) remains unknown. Therefore, this study mainly compares the advantages and disadvantages of delayed FET and immediate FET through retrospective analysis. We analyzed real world data of patients who underwent resuscitation transplantation between October 2019 and July 2021 at the Reproductive Center of Chengdu Jinjiang Hospital for Women's and Children's Health. Propensity score matching was applied to control potential confounding factors. A total of 5,549 patients who received at least one FET were analyzed. Patients undergoing transplantation within 60 days of oocyte retrieval were included in the immediate FET group (n = 1,265) and those undergoing transplantation > 60 days after retrieval were included in the delayed FET group (n = 4,284). Live birth rates between the two groups were comparable (45.25% vs. 45.76%, p = 0.757). Moreover, no difference was observed in the rates of biochemical pregnancy (64.50% vs. 66.80%), clinical pregnancy (55.24% vs. 56.83%), ectopic pregnancy (1.47% vs. 1.39%), early miscarriage (14.41% vs. 16.20%), late miscarriage (2.21% vs. 2.09%), singleton premature delivery (16.67% vs. 18.29%), and neonatal deformity (1.97% vs. 1.80%). After stratifying the patients based on the type of embryo transferred, number of embryos transferred, FET protocol, and good prognosis criteria, live birth rates remained comparable between the two groups (p > 0.05). Pregnancy outcomes were comparable between the immediate and delayed FET groups.

Intrauterine botulinum toxin A administration promotes endometrial regeneration mediated by IGFBP3-dependent OPN proteolytic cleavage in thin endometrium

Adequate endometrial growth is a critical factor for successful embryo implantation and pregnancy maintenance. We previously reported the efficacy of intrauterine administration of botulinum toxin A (BoTA) in improving the endometrial angiogenesis and the rates of embryo implantation. Here, we further evaluated its potent therapeutic effects on the uterine structural and functional repair and elucidated underlying molecular regulatory mechanisms. This study demonstrated that a murine model of thin endometrium was successfully established by displaying dramatically decreased endometrial thickness and the rates of embryo implantation compared to normal endometrium. Interestingly, the expressions of insulin-like growth factor binding protein-3 (IGFBP3) and an active 35 kDa-form of osteopontin (OPN) were significantly reduced in thin endometrium, which were almost fully restored by intrauterine BoTA administration. Neutralization of BoTA-induced IGFBP3 subsequently suppressed proteolytic cleavage of OPN, exhibiting un-recovered endometrial thickness even in the presence of BoTA administration, suggesting that BoTA-induced endometrial regeneration might be mediated by IGFBP3-dependent OPN proteolytic cleavage. Our findings suggest that intrauterine BoTA administration improves the endometrial environment in our murine model with thin endometrium by increasing endometrial receptivity and angiogenesis in a manner dependent on the regulatory effect of IGFBP3 on OPN proteolytic cleavage, proposing BoTA as an efficient therapeutic strategy for the patients with thin endometrium.

Effect of inactivated COVID-19 vaccination on pregnancy outcomes following frozen-thawed embryo transfer: A retrospective cohort study.

To investigate the effect of inactivated coronavirus disease 2019 (COVID-19) vaccination on frozen-thawed embryo transfer (FET) outcomes. This retrospective cohort study enrolled 1,210 patients undergoing FET cycles in a single university-affiliated hospital between July 1, 2021, and May 1, 2022. Of them, 387 women with two full doses of inactivated SARS-CoV-2 vaccines (CoronaVac or BBIBP-CorV) after oocyte retrieval were assigned to the vaccinated group, while 823 were unvaccinated as controls. Propensity score matching and multiple regression analysis were applied to control for baseline and cycle characteristics (19 covariates in total). There were 265 patients in each group after matching. The rates of clinical pregnancy (58.5% vs. 60.8%; P=0.595) and live birth (44.4% vs. 48.8%; P=0.693) were similar between vaccinated and unvaccinated patients, with adjusted odds ratios of 0.89 (95% confidence interval [CI] 0.61-1.29) and 1.31 (95% CI 0.37-4.56), respectively. Consistently, no significant differences were found in serum human chorionic gonadotropin levels as well as biochemical pregnancy, biochemical pregnancy loss, and embryo implantation rates. Based on the time interval from vaccination to FET, vaccinated patients were further subdivided into two categories of ≤2months and >2months, and the outcomes remained comparable. Our study showed that inactivated COVID-19 vaccination in women did not have measurable detrimental impact on implantation performance and live birth outcome during FET treatment cycles. This finding denies the impairment of endometrial receptivity and trophoblast function by vaccine-induced antibodies at the clinical level.

Effect of intramuscular injection of human chorionic gonadotropin on endometrium preparation in frozen-thawed embryo transfer cycle: A randomized clinical trial.

Assisted reproductive therapy (ART) has been developed remarkably in these decades; however, the rate of unsuccessful embryo implantation especially in the frozen-thawed embryo transfer (FET) cycles remains high and is reported up to 70%. The current study was designed to compare the effect of intramuscular injection of hCG on endometrium preparation and embryo implantation, in women undergoing FET compared to the control group. This clinical trial was done on 140 infertile women that underwent FET. The study sample was randomly allocated to the intervention group (two 5000 unit ampoules of hCG were injected intramuscularly before the first dose of progesterone administration) and the control group (without hCG injection). In both groups, 4 days after progesterone administration, the cleavage stage embryos were transferred. The study outcomes were biochemical pregnancy, clinical pregnancy and abortion rate. The average age of intervention and control group was 32.65±6.05 and 33.11±5.36 years, respectively. The basic information between two study groups did not differ significantly. The chemical (30% vs. 17.1%, P=0.073, relative risk (RR)=0.57) and clinical (28.6% vs. 14.3%, P=0.039, RR=0.50) pregnancy rates were higher in the intervention group compared to the control group; these higher ratios were only significant in clinical pregnancy rate. Abortion rate was not significantly (P=0.620) different between the intervention and control groups (4.3% vs. 1.4%, respectively). This study showed that intramuscular injection of 10000 IU hCG before the endometrial secretory transformation phase in cleavage-stage embryo, improves IVF cycle outcomes.

Into the Microscale: Low-input sequencing technologies and applications in medicine

&lt;p&gt;Sequencing technology has undergone major breakthroughs over time and has become indispensable in biological and medical research. Advances in protocols and analysis algorithms allow the analysis of small sample inputs, enabling the characterization of complex networks that govern biological processes in physiology and pathology, driving the development of precision medicine and targeted therapy. In this review, we comprehensively summarize low-input sequencing technologies that include methods for profiling the genome, epigenome, transcriptome, translatome, RNA modification, RNA-RNA interaction, RNA-protein interaction, and multi-omics. The key steps and innovations in different protocols are highlighted, and their advantages, limitations, and scope of application are described. With a focus on the impact of low-input sequencing technologies in biomedical fields, including embryonic development, prenatal and preimplantation genetic testing, oncology and immunology, and pandemic research, we discuss their potential to improve embryo implantation rates, prevent birth defects, develop prospective therapies, and predict prognosis. Lastly, we discuss current limitations and future prospects, providing new insights for medical research.&lt;/p&gt;