Comparison of pregnancy outcomes among patients of different ages who underwent frozen-thawed high-quality single blastocyst transfer.

OBJECTIVE: To investigate the feasibility of performing frozen-thawed high-quality single blastocyst transfer in women of different ages. METHODS: A total of 1,279 women were divided into four groups: a 38-40-year-old group (n = 147), 35-37-year-old group (n = 164), 30-34-year-old group (n = 483), and < 30-year-old group (n = 485). Intergroup comparisons of baseline characteristics and pregnancy and neonatal outcomes were made. RESULTS: The clinical pregnancy rate (47.6%), and live birth rate (34.0%) in the 38-40-year-old group were significantly lower than those in the 30-34-year-old group (64.4%, 50.9%, respectively; all P < 0.001) and < 30-year-old group (62.9%, 50.7%, respectively; all P < 0.001). However, the 35-37-year-old group did not differ from the other three groups in these two dimensions (all P > 0.05). Moreover, there were no differences in the rates of biochemical pregnancy, miscarriage, or obstetric or neonatal complications among the four groups (all P > 0.05). According to the multivariate logistic regression analysis, the 35-37-year-old group was not associated with non-live birth outcomes, adverse pregnancy outcomes, or obstetric or neonatal complications. However, being 38-40 years of age was a risk factor for non-live birth (OR = 2.121, 95% CI: 1.233-3.647) and adverse pregnancy outcomes (OR = 1.630, 95% CI: 1.010-2.633). Post hoc power analysis showed that the study was sufficiently powered to detect meaningful differences. CONCLUSION: Frozen-thawed high-quality single blastocyst transfer produces the same satisfactory pregnancy outcomes for women aged 35-37 years as younger patients. Future prospective randomized controlled studies with larger populations are needed to verify the feasibility and safety of this method.

Association between blood lead levels and unfavorable IVF outcomes: potential involvement of endoplasmic reticulum stress response in granulosa cells.

PURPOSE: To investigate the relationship between blood lead levels (BLLs) and IVF clinical outcomes in infertile females and to further explore the possible involvement of granulosa cell (GC) endoplasmic reticulum (ER) stress in the process. METHODS: One hundred twenty-three infertile women undergoing IVF cycles were included in the current study. All participants were divided into three (low, medium, and high) groups determined by BLL tertiles. Gonadotropin releasing hormone (GnRH) agonist regimen for ovarian stimulation was used for all patients, with follicular fluids being collected on the day of oocyte retrieval. Lactate dehydrogenase (LDH) levels in follicular fluid and the endoplasmic reticulum stress-signaling pathway of granulosa cells (GCs) were examined. RESULTS: The oocyte maturation rate and high-quality embryo rate on cleaved stage decreased significantly as BLL increased. For lead levels from low to high, live birth rate (68.29%, 56.10%, 39.02%; P=0.028) showed negative correlations with BLLs. Also, follicular fluid Pb level and LDH level was significantly higher in the high lead group versus the low group. Binomial regression analysis revealed significant negative correlation between BLLs and live birth rate (adjusted OR, 0.38; 95% CI, 0.15-0.95, P=0.038). Further analysis of the endoplasmic reticulum stress (ER stress) signaling pathway of GCs found that expressions of GRP78, total JNK, phosphorylated JNK, and CHOP increased and BCL-2 decreased with increasing BLLs. CONCLUSIONS: BLLs are negatively associated with final clinical outcomes in IVF patients that may be related to increased ER stress response and GC apoptosis. Thus, reducing Pb exposure before IVF procedures may improve final success rates.

Effects of organochlorine pesticides on human and rat 17ß-hydroxysteroid dehydrogenase 1 activity: Structure-activity relationship and in silico docking analysis.

The objective of this study was to examine the effect of 11 organochlorine pesticides on human and rat 17ß-Hydroxysteroid dehydrogenase 1 (17ß-HSD1) in human placental and rat ovarian microsome and on estradiol production in BeWo cells. The results showed that the IC50 values for endosulfan, fenhexamid, chlordecone, and rhothane on human 17ß-HSD1 were 21.37, 73.25, 92.80, and 117.69 µM. Kinetic analysis revealed that endosulfan acts as a competitive inhibitor, fenhexamid as a mixed/competitive inhibitor, chlordecone and rhothane as a mixed/uncompetitive inhibitor. In BeWo cells, all insecticides except endosulfan significantly decreased estradiol production at 100 µM. For rats, the IC50 values for dimethomorph, fenhexamid, and chlordecone were 11.98, 36.92, and 109.14 µM. Dimethomorph acts as a mixed inhibitor, while fenhexamid acts as a mixed/competitive inhibitor. Docking analysis revealed that endosulfan and fenhexamid bind to the steroid-binding site of human 17ß-HSD1. On the other hand, chlordecone and rhothane binds to a different site other than the steroid and NADPH-binding site. Dimethomorph binds to the steroid/NADPH binding site, and fenhexamid binds to the steroid binding site of rat 17ß-HSD1. Bivariate correlation analysis showed a positive correlation between IC50 values and LogP for human 17ß-HSD1, while a slight negative correlation was observed between IC50 values and the number of HBA. ADMET analysis provided insights into the toxicokinetics and toxicity of organochlorine pesticides. In conclusion, this study identified the inhibitory effects of 3-4 organochlorine pesticides and binding mechanisms on human and rat 17ß-HSD1, as well as their impact on hormone production.

Comparison of frozen-thaw blastocyst transfer strategies in women aged 35-40 years: a retrospective study.

Objective: To compare the effects of five different frozen-thaw embryo transfer (FET) strategies in women aged 35-40 years. Methods: Data from 1,060 patients were divided into five groups according to the number and quality of transferred blastocysts: a high-quality single blastocyst group (group A, n= 303), a high-quality double blastocysts group (group B, n= 176), a high-quality plus poor-quality double blastocysts group (group C, n= 273), a poor-quality double blastocysts group (group D, n= 189), and a poor-quality single blastocyst group (group E, n= 119). Comparative analyses were then performed between groups with regard to primary conditions, pregnancy, and neonatal outcomes. Results: Group A had the lowest twin pregnancy rate (1.97%) and incidence of low-birth-weight infants (3.45%), which were significantly different from groups B, C, and D. In addition, the preterm birth rate (7.89%), neonatal birth weight (3300 g [3000, 3637.5]), and neonatal birth age (39.14 weeks [38.43, 39.61]) in group A were different from those in groups B and C. Double blastocyst transfer (DBT) was associated with a 20.558-fold (Risk Ratio [RR]=20.558, 95% confidence interval [CI], 6.628-63.763) and 3.091-fold (RR=3.091, 95% CI, 1.69-5.653) increased risk of twin pregnancy and preterm delivery in unadjusted analysis, respectively, when compared with single blastocyst transfer (SBT). In the adjusted analysis, we observed similar risk estimates (adjusted RR=26.501, 95% CI, 8.503-82.592; adjusted RR=3.586, 95% CI, 1.899-6.769). Conclusion: Although, high-quality SBT resulted in a lower live birth rate than high-quality DBT, it also significantly reduced the risk of adverse pregnancies, thus resulting in more benefits for both the mother and baby. Collectively, our data indicate that high-quality SBT remains the optimal FET strategy for women aged 35-40 years and warrants further clinical application.

A negative association between triglyceride glucose-body mass index and testosterone in adult males: a cross-sectional study.

Background and objectives: Insulin resistance (IR) is closely related to the decline or deficiency of testosterone in males. Triglyceride glucose-body mass (TyG-BMI) is considered to be a novel indicator of IR. We conducted this analysis to investigate the association between TyG-BMI and male testosterone, and to explore whether its ability to predict testosterone deficiency is superior to HOMA-IR and TyG. Methods: This was a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES, 2011-2016). The TyG-BMI index was calculated from serum triglyceride, fasting plasma glucose and BMI. The association of TyG-BMI with male testosterone was estimated by weighted multivariable regression. Results: We included 3394 participants for the final analysis. After adjusting for confounders, TyG-BMI was found to show an independent negative association with testosterone (ß=-1.12, 95%CI: -1.50, -0.75, P<0.0001). Multivariate-adjusted beta also showed testosterone levels were significantly lower in the two highest TyG-BMI group (Q3, Q4) compared to the lowest group (Q1). Similar results were seen in all of the subgroup populations by stratified analysis (all P-interaction >0.05). Furthermore, ROC curve analysis indicated that the area under the curve of TyG-BMI index (0.73, 95% CI: 0.71, 0.75) was larger than that of HOMA-IR index (0.71, 95% CI: 0.69, 0.73) and TyG index (0.66, 95% CI: 0.64, 0.68). Conclusion: Our result suggested a negative association between TyG-BMI index and testosterone in adult males. The predictability of the TyG-BMI index for testosterone deficiency is better than that of HOMA-IR index and TyG index.

Pubertal lead exposure affects ovary development, folliculogenesis and steroidogenesis by activation of IRE1α-JNK signaling pathway in rat.

Epidemic studies showed that lead exposures are associated with various female reproductive dysfunctions, including infertility, miscarriage, preterm delivery, and early menopause. However, the mechanism involved is still unclear. In the current study, SD rats were exposed to lead at doses of 0, 5, 25, 50 or 250 mg/L through drinking water from postnatal day 21-56. Lead exposures did not affect the body weight or ovary weight. However, the puberty initiation (ages by which vagina opens and estrous cycle occurs) was significantly delayed by as many as 5.8 and 6.8 days respectively (P < 0.05). Also, lead exposures disrupted the estrous cycles, reduced the numbers of primordial and primary follicles and increased the number of atretic follicles by adult. Furthermore, for the highest does group, serum levels of progesterone and testosterone decreased by 80.2% (P < 0.01) and 49.9% (P < 0.05) respectively, while estradiol level increased by 69.8% (P < 0.01). Western blot analyses indicated that lead exposures specifically down-regulated the expressions of steroidogenic protein STAR, CYP17A1, and HSD3B1, while up-regulated FSHR and CYP19A1. Also, the exposure stimulated the endoplasmic reticulum stress (ERS)-related IRE1α-JNK signaling pathway members. Such activation may also result in apoptosis since the death-signaling molecules CHOP and cleaved-CASP3 were up-regulated while BCL2 was down-regulated. In conclusion, lead exposure during juvenile and puberty significantly affected ovary development and functions. The effects may relate to ERS response since the 6 members related to the pathway were all consistently activated.

Chk1/2 inhibitor AZD7762 blocks the growth of preantral follicles by inducing apoptosis, suppressing proliferation, and interfering with the cell cycle in granulosa cells.

BACKGROUND: Checkpoint kinases 1/2 (Chk1/2) have an important role in somatic cell development and oocyte meiotic maturation. However, the role of Chk1/2 in folliculo-genesis has not been fully elucidated. The aim of this study was to assess the effects of Chk1/2 inhibition on ovarian folliculogenesis and granulosa cell development in mice. METHODS: Preantral follicles (100-120 µm) and granulosa cells from pre-ovulatory follicles (pre-GCs) of mice were isolated and cultured with or without Chk1/2 inhibitor AZD7762. Preantral follicles were cultured for 96h. Then, follicle morphology and fol-licular growth were assessed every 48h. Granulosa cells were cultured for 48h with or without AZD7762, after which cell apoptosis, cell proliferation, and cell cycle analysis were assessed; meanwhile, the mRNA expression of PCNA and Bax were measured by real-time RT-PCR, and PCNA and Bax protein were measured by Western blot. RESULTS: Compared with control follicles, AZD7762 inhibited growth of preantral folli-cles (P<0.05). Furthermore, inhibition of Chk1/2 significantly induced apoptosis (P<0.05) and inhibited the proliferation of granulosa cells (P<0.01), arrested cell cycle at S and G2/M phases, and decreased G1 phase fraction (P<0.001). Also, the expres-sion of PCNA mRNA and protein were reduced (P<0.01), while Bax mRNA and pro-tein were increased (P<0.05) post AZD7762 treatment in granulosa cells. CONCLUSIONS: This study revealed that Chk1 and Chk2 have a crucial role during preantral follicular development by regulating the proliferation and apoptosis of granu-losa cells.

Does vitamin D level associate with pregnancy outcomes in Chinese women undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer? A retrospective cohort study.

AIM: To explore the relationship between serum 25(OH)D level and pregnancy outcomes (clinical pregnancy rate [CPR] and live birth rate [LBR]) in Chinese women receiving in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI)-embryo transfer (ET) (IVF/ICSI-ET). METHODS: A total of 612 patients included in the study were divided into four cohorts according to serum 25(OH)D with the threshold of 20 ng/ml, 25 ng/ml, 30 ng/ml, and retrospectively analyzed. RESULTS: None of the baseline characteristics of participants was significantly different in the four cohorts except gravid status. The trend of 25(OH)D concentration was positively correlated with CPR and LBR. The younger (age: p < 0.001 both in CPR and LBR) women with primary infertility (infertility type: p = 0.004 in LBR) were more likely to get a better pregnancy outcome under the same 25(OH)D concentration stages. As shown on heatmap plots, CPR, and LBR were significantly increased for 25(OH)D concentrations above 30.00 ng/ml and women younger than 30 years old. The adjusted binary logistic regression and restricted cubic spline (RCS) showed that there existed a nonlinear positive correlation between 25(OH)D concentration and pregnancy outcome (CPR and LBR) (Pnonlinear < 0.001, respectively). The women with a sufficient 25(OH)D concentration (30 ng/ml) had 1.07 (clinical pregnancy) and 1.05 (live birth) times higher successful birth outcomes compared to women with an insufficient 25(OH)D concentration (25 ng/ml). (OR25 ng/ml, ref = 30 ng/ml [95% CI] = 0.935 [0.932-0.938] and 0.947 [0.945-0.950], p < 0.001, respectively). CONCLUSION: In Chinese women receiving IVF/ICSI-ET, the serum level of 25(OH)D demonstrated a nonlinear positive correlation with pregnancy outcomes (CPR and LBR), with stronger correlations above 25 ng/ml and worse yields below 30 ng/ml. However, it could not yet be considered different in distinct ages.

Comparison of frozen-thawed embryo transfer strategies for the treatment of infertility in young women: a retrospective study.

Objective: To investigate transfer strategies in the frozen-thawed embryo transfer (FET) cycle. Methods: The clinical data of 1,652 FET patients were divided into five groups according to the number and quality of the transferred blastocyst: high-quality single blastocyst group (group A, n = 558), high-quality plus poor-quality double blastocyst group (group B, n = 435), poor-quality double blastocyst group (group C, n = 241), high-quality double blastocyst group (group D, n = 298), and poor-quality single blastocyst group (group E, n = 120). Inter-group comparison analyses of primary conditions, pregnancy outcomes and neonatal outcomes were then performed. Results: Group A had the highest embryo implantation rate (67.38%), significantly different from the implantation rates of the other four groups. The gemellary pregnancy rate (1.60%), preterm birth rate (5.58%), neonatal birth weight (3,350g [3,000g, 3,650g]), neonatal birth age (39.57 weeks [38.71, 40.34]), and incidence of low birth weight (7.02%) in group A were different from those in groups B, C, and D, but did not significantly differ from those in group E. Moreover, the proportions of male infants born in groups A (56.86%) and D (59.41%) were significantly higher than those in the other three groups. Double blastocyst transfer (0.528, 95% CI [0.410-0.680], P < 0.001) and high-quality blastocyst transfer (0.609, 95% CI [0.453-0.820], P = 0.001) were found to be protective factors for live birth. In addition, double blastocyst transfer was also the largest risk factor for pregnancy complications (3.120, 95% CI [2.323-4.190], P < 0.001) and neonatal complications (2.230, 95% CI [1.515-3.280], P < 0.001), especially for gemellary pregnancy (59.933, 95% CI [27.298-131.58], P < 0.001) and preterm birth (3.840, 95% CI [2.272-6.489], P < 0.001). Based on the ROC curves, a double blastocyst transfer could predict gemellary pregnancy reliably with a high area under the curve (AUC = 78.53%). Additionally, a double blastocyst transfer could effectively predict a high risk of pregnancy complications (AUC = 65.90%), neonatal complications (AUC = 64.80%) and preterm birth (AUC = 66.20%). Conclusion: The live birth rate of frozen-thawed high-quality single blastocyst transfer is lower than that of double high-quality blastocyst transfer, which can significantly increase the embryo implantation rate. High-quality single blastocyst transfer also significantly lowers the risk of gemellary pregnancy, preterm birth, and low birth weight, and can significantly improve maternal and infant outcomes. After weighing the pros and cons of live birth with pregnancy and neonatal complications, the authors believe that high-quality single blastocyst transfer is the optimal FET strategy for young women and is worthy of further clinical application. Despite this recommendation, high-quality single blastocyst transfer can increase the risk of monozygotic twins, as well as significantly increase the proportion of male infants born.

Knockdown of Chk1 inhibits proliferation and promotes apoptosis in mouse granulosa cells and its regulation mechanism by miR-15a and miR-16.

Checkpoint kinase 1 (Chk1) is a protein kinase which preserves the genome integrity, and works as an evolutionally conserved DNA damage response and cell cycle checkpoint. However, the functional roles and regulatory mechanism of Chk1 in mouse granulosa cells (GCs) have not been fully elucidated. In this study, by RNA interfering, Chk1 gene was knocked down in GCs. Knockdown of Chk1 inhibited proliferation and increased apoptosis of GCs (p < 0.05), respectively; in addition, cell cycle of GCs was arrested at S and G2/M phases. Further qRT-PCR results showed that cell cycle factors (Cyclin B1 and Cyclin D 1) and a marker gene of proliferation (PCNA) were downregulated (p < 0.001), while apoptotic factors (p53b, p21, caspase-3, and Bax) were upregulated (p < 0.01), which suggested that knockdown of Chk1 may inhibit proliferation, regulate cell cycle, and promote apoptosis at the transcriptional level in GCs. In vitro studies showed a negative correlation between Chk1 mRNA and miR-16 expression during follicular development. To elucidate the relationship between Chk1 and miR-15a/16, luciferase reporter plasmids were constructed and luciferase assays revealed that both miR-15a and miR-16 could bind to the 3' UTR of Chk1 mRNA, and significantly downregulate the protein level of Chk1 (p < 0.01), while miR-16, not miR-15a, could significantly decrease the mRNA level of Chk1 (p < 0.05). This result indicated that miR-16 directly induced Chk1 mRNA destabilization, while miR-15a regulated Chk1 expression through translational repression. Taken together, this study uncovered the roles of Chk1 in mouse granulosa cells and its regulation by miR-15a and miR-16 through different mechanisms.

Noninvasive Chromosome Screening for Evaluating the Clinical Outcomes of Patients With Recurrent Pregnancy Loss or Repeated Implantation Failure.

This retrospective cohort study explores whether noninvasive chromosome screening (NICS) for aneuploidy can improve the clinical outcomes of patients with recurrent pregnancy loss (RPL) or repeated implantation failure (RIF) in assisted reproductive technology. A total of 273 women with a history of RPL or RIF between 2018 and 2021 were included in this study. We collected data of all oocyte retrieval cycles and single blastocyst resuscitation transfer cycles. For the patients experiencing RPL, NICS reduced the miscarriages rate per frozen embryo transfer (FET), improved the ongoing pregnancies rate and live birth rate: 17.9% vs 42.6%, adjusted OR 0.39, 95% CI 0.16-0.95; 40.7% vs 25.0%, adjusted OR 2.00, 95% CI 1.04-3.82; 38.9% vs 20.6%, adjusted OR 2.53, 95% CI 1.28-5.02, respectively. For the patients experiencing RIF, the pregnancy rates per FET in the NICS group were significantly higher than those in the non-NICS group (46.9% vs. 28.7%, adjusted OR 2.82, 95% CI 1.20-6.66). This study demonstrated that the selection of euploid embryos through NICS can reduce the miscarriage rate of patients experiencing RPL and improve the clinical pregnancy rate of patients experiencing RIF. Our data suggested NICS could be considered as a possibly useful screening test in clinical practice.

A precise and efficient adenine base editor.

Adenine base editors (ABEs) are novel genome-editing tools, and their activity has been greatly enhanced by eight additional mutations, thus named ABE8e. However, elevated catalytic activity was concomitant with frequent generation of bystander mutations. This bystander effect precludes its safe applications required in human gene therapy. To develop next-generation ABEs that are both catalytically efficient and positionally precise, we performed combinatorial engineering of NG-ABE8e. We identify a novel variant (NG-ABE9e), which harbors nine mutations. NG-ABE9e exhibits robust and precise base-editing activity in human cells, with more than 7-fold bystander editing reduction at some sites, compared with NG-ABE8e. To demonstrate its practical utility, we used NG-ABE9e to correct the frequent T17M mutation in Rhodopsin for autosomal dominant retinitis pigmentosa. It reduces bystander editing by ∼4-fold while maintaining comparable efficiency. NG-ABE9e possesses substantially higher activity than NG-ABEmax and significantly lower bystander editing than NG-ABE8e in rice. Therefore, this study provides a versatile and improved adenine base editor for genome editing.

Embryo selection through non-invasive preimplantation genetic testing with cell-free DNA in spent culture media: a protocol for a multicentre, double-blind, randomised controlled trial.

INTRODUCTION: Morphological evaluation is used to select embryos for in vitro fertilisation. However, it does not fully reflect the implantation potential. Preimplantation genetic testing for aneuploidies (PGT-A) can detect embryonic aneuploidy, but biopsy procedure is invasive. Currently, a non-invasive PGT (ni-PGT) approach using spent medium is being evaluated. However, the clinical benefit of ni-PGT has not been clearly demonstrated. A multicentre randomised trial is needed to verify whether ni-PGT can be an new effective tool for evaluating embryos. METHODS AND ANALYSIS: Overall, 1148 couples aged 35~42 (women) receiving in vitro fertilization-intracytoplasmic sperm injection are planned to be enrolled. Couples will be digitally randomised to (1) ni-PGT and (2) conventional morphology groups at a 1:1 treatment ratio. The primary outcome will be the ongoing pregnancy rate related to the first transfer cycle within 6 months after oocyte retrieval. ETHICS AND DISSEMINATION: The study protocol is approved by the Ethics Committee of Peking University Third Hospital and the participating hospitals. The results will be disseminated through international conferences and scientific journals. TRIAL REGISTRATION NUMBER: NCT04339166.

Can SpRY recognize any PAM in human cells?

The application of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated proteins (Cas) can be limited due to a lack of compatible protospacer adjacent motif (PAM) sequences in the DNA regions of interest. Recently, SpRY, a variant of Streptococcus pyogenes Cas9 (SpCas9), was reported, which nearly completely fulfils the PAM requirement. Meanwhile, PAMs for SpRY have not been well addressed. In our previous study, we developed the PAM Definition by Observable Sequence Excision (PAM-DOSE) and green fluorescent protein (GFP)|-reporter systems to study PAMs in human cells. Herein, we endeavored to identify the PAMs of SpRY with these two methods. The results indicated that 5'-NRN-3', 5'-NTA-3', and 5'-NCK-3' could be considered as canonical PAMs. 5'-NCA-3' and 5'-NTK-3' may serve as non-priority PAMs. At the same time, PAM of 5'-NYC-3' is not recommended for human cells. These findings provide further insights into the application of SpRY for human genome editing.

Comparison of pregnancy and neonatal outcomes of intracytoplasmic sperm injection performed with frozen versus fresh testicular sperm.

Background: It remains controversial whether there is a difference in the prognosis of intracytoplasmic sperm injection (ICSI) using frozen or fresh testicular sperm in patients with obstructive azoospermia (OA). Moreover, in the available studies, few have tracked neonatal outcomes. This study aimed to compare the pregnancy and neonatal outcomes of ICSI using cryopreserved sperm versus fresh sperm collected by testicular sperm aspiration (TESA). Methods: A total of 317 OA patients treated with ICSI in a university affiliated hospital from January 2016 to December 2020 were included in this study. The participants were divided into two groups according to the type of sperm used for ICSI: frozen sperm group (n=154) and fresh sperm group (n=163). The pregnancy and neonatal outcomes of the two groups were compared. Results: The data produced by this study showed no significant statistical difference in the 2 pronuclei (2PN) fertilization rate, 2PN cleavage rate, high-quality blastocyst rate, and the average number of transferred embryos in the frozen and fresh sperm groups. Similarly, no difference was found in implantation rate, clinical pregnancy rate, multiple pregnancy rate, miscarriage rate, premature delivery rate, live birth rate, and gender ratio at birth (P>0.05). The average newborn birth weight was similar in both groups (2,932.61±728.40 vs. 3,100.32±515.64 g, respectively) (P>0.05). A higher incidence of low birthweight (LBW) newborns was found in the frozen sperm group (20.91% vs. 8.49%) (P<0.05). Multiple logistic regression analysis showed that LBW is related to single or twin pregnancies (P<0.01), but not sperm (frozen or fresh) (P>0.05). We further analyzed the twin and single pregnancies in the two groups separately, and found that the incidences of LBW were both similar (P>0.05). There was no difference in the Apgar scores at 1 min and 5 min after birth between the two groups (P>0.05). Conclusions: The use of frozen testicular sperm by TESA was efficient for men with OA. There were similar pregnancy and neonatal outcomes following TESA-ICSI using frozen or fresh sperm in this retrospective study. Prospective investigations are needed for further validation.

Investigate the effect of COVID-19 inactivated vaccine on sperm parameters and embryo quality in in vitro fertilization.

Since the reproductive toxicity of COVID-19 vaccines have not been assessed in previous clinical trials, and studies have shown that SARS-CoV-2 is associated with a decrease in sperm parameters. Although it has been reported that the mRNA SARS-CoV-2 vaccines do not adversely affect semen parameters, whether this conclusion applies to inactivated vaccines remains unclear. Here, we conducted a study among patients who accepted in vitro fertilization (IVF) at the reproductive centre between June and August of 2021. In the enrolled cases, men who have completed two doses of COVID-19 inactivated vaccine were included in "vaccine group" (N = 105), and those who were not vaccinated were included in "control group" (N = 155). In this study, we compare the sperm parameters and embryo quality between these two groups. Our data showed that the sperm parameters were similar in terms of volume, sperm concentration, sperm count, progressive motility, total motility and total motile sperm count between these two groups. Similarly, no significant differences were observed in IVF outcomes. The mean number of 2PN, cleavage-stage embryos, blastocysts, and good-quality blastocysts was 8.59 ± 4.47, 5.06 ± 3.17 and 2.08 ± 1.79 in vaccine group, 7.75 ± 4.14, 4.34 ± 3.06 and 1.74 ± 1.54 in control group, respectively. The high-quality blastocyst rate was 41.05% (218 of 531) in vaccine group and 40.03% (269 of 672) in control group (p > 0.05). In addition, no differences were observed in biochemical and clinical pregnancy rates between the two groups. In summary, our results revealed that COVID-19 inactivated vaccine administration exhibited no negative effect on sperm parameters and embryo quality in IVF.

Estradiol (E 2) Reduction Adversely Affect the Embryo Quality and Clinical Outcomes of In Vitro Fertilization and Embryo transfer (IVF-ET).

Objective: The purpose of this study was to explore the influence of decreased serum estradiol (E 2) levels during controlled ovarian hyperstimulation (COH) on in vitro fertilization and embryo transfer (IVF). Methods: The clinical data of 300 IVF-ET cycles with patients were analyzed retrospectively. According to the presence of falling E 2 level during the COH, we divided all subjects into two groups: the E 2 levels fall group (n = 120, group A) and the control group (n = 180, group B). In group A, there were 57 patients with falling E 2 with drug dosage reduction. The other 63 patients experienced the decreased E 2 level spontaneously. The clinical and laboratory variables in the groups were compared. Receiver operator characteristic (ROC) curve analyses were carried out in order to evaluate the predict value of E 2 level on the day of human chorionic gonadotropin (hCG) administration on IVF outcomes. Results: Duration and total dosage of gonadotropin (Gn) used were statistically more in group A than in group B (P < 0.001). The high-quality embryo rate was significantly lower in group A (P = 0.048). Women in group A had lower clinical pregnancy rate (P = 0.029), live birth rate (P < 0.001), ongoing pregnancy rate (P = 0.001), and higher early abortion rates (P = 0.008) than group B. Women with spontaneously falling E 2 group had a higher BMI index than those in the drug dosage reduction group (P = 0.001). More dosage and longer duration of Gn in spontaneously falling E 2 group than in the drug dosage reduction group (P < 0.01). There were no differences in clinical outcomes between the two types of E 2 decreased groups. Results from ROC showed an E 2 level <1987.5 pg/ml on the hCG day might predict early abortion in this study. The sensitivity was 58.4% and the specificity was 78.9%. In addition, an E 2 level >2020 pg/ml on the hCG day might be an index to predict live birth. The sensitivity was 57.0% and the specificity was 61.7%. Conclusions: Reduction of E 2 during COH might adversely affect the clinical pregnancy, early abortion, and ongoing pregnancy of IVF-ET.

Comparative study on risk of birth defects in singleton ART birth under high levels of estrogen after fresh embryo transfer and frozen embryo transfer.

OBJECTIVE: To investigate whether high estrogen (E2) levels caused by controlled ovarian hyperstimulation affect the birth defect rate in singleton assisted reproductive technology (ART) birth after conceived by fresh embryo transfer and frozen embryo transfer (FET). METHODS: This was a retrospective cohort study. A total of 581 women with singletons, as well as those who have become pregnant and have had an unwanted abortion under high E2 levels on trigger day were divided into three groups. Group A received FET and the E2 levels on trigger day were higher than 5000 pg/ml. Group B received fresh embryo transfer and the E2 levels were between 3000 and 5000 pg/ml. Group C received FET and the E2 levels were between 3000 and 5000 pg/ml. RESULTS: There were no significant differences in birth weight, delivery mode, preterm birth rate, and fetal sex between the three groups (p > .05). Birth defect rate in Group B was higher than that in Group A and C, and the rate between Group B and C had significant differences (p < .05). After adjusting for maternal age, BMI, and type of infertility, only a FET cycle is significantly associated with decreased birth defect rate. CONCLUSION: Fresh embryo transfer under supraphysiological level of estrogen exposure may increase the birth defect rate of ART singletons. Even after prenatal screening and diagnosis, a part of birth defect could not be detected during pregnancy. When the estrogen levels on trigger day were no lower than 3000 pg/ml, FET should be advocated to reduce the occurrence of such risk.

The feasibility of switching from IVF to IVM combined with all-blastocyst-culture and transfer for patients with ovarian hyperstimulation syndrome tendency.

OBJECTIVE: To investigate the feasibility of switching from in vitro fertilization (IVF) to in vitro maturation (IVM) combined with all-blastocyst-culture and transfer as a supplementary infertility treatment in patients with ovarian hyperstimulation syndrome (OHSS) tendency METHODS: Retrospective cohort study including 184 patients who switched from IVF and underwent 192 IVM cycles between January 2016 and December 2020. The outcomes were compared between cleavage-stage embryo transfer (group A, n = 74) and blastocyst-stage transfer (group B, n = 52) groups. RESULTS: The OHSS rate is 0%. 66 cycles were canceled for transfer. Among the 126 transfer cycles, number of retrieved oocytes, proportion of metaphase II oocytes, cleavage rate, and proportion of high-quality embryos on day 3 post-fertilization are significantly lower in group A than that in group B. On the contrary, number of transferred embryos is significantly lower in group B than that in group A, whereas the rates of implantation, clinical pregnancy, and live births are significantly higher in group B than that in group A. CONCLUSION: Timely switching to IVM combined with all-blastocyst-culture and transfer for patients undergoing controlled ovarian hyperstimulation and exhibiting characteristics of OHSS tendency is feasible as a supplementary infertility treatment.

Two high-fidelity variants: efSaCas9 and SaCas9-HF, which one is better?

CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated endonuclease Cas9) nucleases have been widely applied for genome engineering. Staphylococcus aureus Cas9 (SaCas9) is compact, which can be packaged in AAV (adeno-associated virus) vector for in vivo gene editing. While, wild-type SaCas9 can induce unwanted off-target mutations and substantially limits the applications. So far, there are two reported SaCas9 variants with high-fidelity, including efSaCas9 from our previous study and SaCas9-HF. However, it remains unknown which one possessing the better fidelity and higher activity. Here, we performed a parallel comparison of efSaCas9 and SaCas9-HF in human cells through fluorescent reporter system and target deep sequencing, respectively. The results demonstrated that efSaCas9 possesses higher cleavage activity and fidelity than SaCas9-HF at the most endogenous sites in human cells. Collectively, our study provides insights for the rational selection of suitable SaCas9 for human genome editing.