Human Reproduction

Structured abstractO_ST_ABSObjectiveC_ST_ABSThis study aims to evaluate antimullerian hormone (AMH) levels across Polycystic Ovary Syndrome (PCOS) phenotypes (A, B, C, D) based on the Rotterdam diagnostic criteria. Data SourcesA systematic review and meta-analysis were conducted following PRISMA guidelines. PubMed, Embase, ScienceDirect, and Web of Science were searched for studies published between January 2009 and June 2024. Study Eligibility CriteriaStudies reporting AMH levels stratified by PCOS phenotypes based on the Rotterdam criteria, along with population characteristics and AMH measurement methods, were included. Animal studies, reviews, case reports, opinion articles, letters to the editor, other non-original research. and those lacking complete phenotype stratification were excluded. Study Appraisal and Synthesis MethodsStudy quality was assessed using the ROBINS-E tool. Primary outcomes included mean AMH levels across phenotypes, analyzed as tAMH (without assay differentiation) and bcAMH (Beckman Coulter Gen II assay). Secondary outcomes included age and BMI by phenotype. Random-effects meta-analysis was used to calculate mean levels and standardized mean differences (SMD) with 95% confidence intervals (CI). Heterogeneity was assessed using the I{superscript 2} statistic. ResultsForty-nine studies involving 15,535 subjects revealed that AMH levels vary significantly by phenotype, being highest in A, followed by D, C, and B. For phenotype A: tAMH=9.87 ng/mL (SMD 2.97, CI 9.29-10.48); bcAMH=11.49 ng/mL (SMD 3.06, CI 10.47-12.61). For phenotype B: tAMH=5.71 ng/mL (SMD 0.98, CI 4.96-6.57); bcAMH=6.25 ng/mL (SMD 1.36, CI 5.20-7.51). There were no significant differences in age or BMI among phenotypes. High heterogeneity suggests additional factors influence AMH levels beyond phenotypic categories. ConclusionsAMH levels are elevated in PCOS and vary across phenotypes, underscoring their potential to improve PCOS subtype characterization and guide management strategies. The findings highlight the need for standardizing AMH measurement techniques for consistent clinical application.

BackgroundPolycystic ovary syndrome is one of the most frequent endocrinological problems causing infertility in women worldwide. The main problem in these women is hyperandrogenism and/or chronic oligo/anovulation, which leads to infertility. In this systematic review and meta-analysis, we aimed to investigate the efficacy of a relatively new drug for ovulation induction, letrozole, by comparing it to the first line of treatment for ovulation induction, clomiphene citrate. MethodsA literary search was conducted in three databases and included randomized clinical trials comparing letrozole and clomiphene citrate for ovulation induction for women with polycystic ovary syndrome. The diagnosis of polycystic ovary syndrome was determined according to the Rotterdam criteria. We pooled data using a random-effects model. ResultsOur search provided a total of 1,994 articles, of which we included 25 studies. In the letrozole group, endometrial thickness was significantly higher (Mean Difference=1.70, Confidence Interval: 0.55-2.86; Heterogeinity: I2=97%, p-value=0.008); odds for ovulation (Odds Ratio=1.8, Confidence Interval: 1.21-2.69; Heterogeinity: I2=51%, p-value=0.010) and pregnancy (Odds Ratio=1.96, Confidence Interval: 1.37-2.81; Heterogeinity: I2=32%, p- value=0.002) were significantly higher; the resistance index of subendometrial arteries was significantly lower (Mean Difference=-0.15, Confidence Interval: -0.27- -0.04; Heterogeneity: I2=92%, p-value=0.030). ConclusionWomen with polycystic ovary syndrome treated with letrozole for ovulation induction had higher ovulation and pregnancy rates, their endometrium became thicker, the resistance index of subendometrial arteries was lower. The lower resistance index of the subendometrial arteries can improve intrauterine circulation, which may provide better circumstances for embryo implantation and development.

BackgroundIndependent of endometrial timing, there are molecular causes of implantation failure that disrupt the endometrial transcriptome in the mid-secretory phase. However, the molecular mechanisms disrupting the window of implantation (WOI) remain poorly understood. The molecular heterogeneity of this endometrial disruption must be characterized to develop personalized and more accurate diagnostic tools for preventive medicine, particularly for patients with a high risk of endometrial failure. Objective(s)This study aimed to stratify and characterize the disrupted WOI patterns using endometrial timing-corrected whole gene expression and artificial intelligence (AI) models in in vitro fertilization (IVF) patients undergoing hormone replacement therapy (HRT). Study designThis multicenter prospective study was conducted between January 2019 and August 2022. Endometrial biopsies were collected during the mid-secretory phase for whole endometrial transcriptome analysis using RNA-Sequencing. To identify disruptions in the WOI, the transcriptomic variation due to cyclic endometrial tissue changes was removed. Out of 195 biopsies sequenced, 131 were derived from patients that met the clinical criteria to be classified as having a poor prognosis ([&ge;]3 implantation failures, n=32) or good prognosis (<3 implantation failures, n=99). The 131 patients were randomly allocated to training (n=105) and test (n=26) sets for biomarker signature discovery and assessment of predictive performance, respectively. The reproductive outcomes of the single embryo transfer immediately after biopsy collection were analyzed. Differential gene expression and functional analyses were performed to characterize molecular profiles. Finally, a quantitative polymerase chain reaction (qPCR) assay was used to corroborate the differential expression of six potential biomarkers. ResultsWith the dichotomous clinical classification of poor or good reproductive prognosis, there was no transcriptomic distinction between patients with a history of implantation failures during HRT endometrial preparation. Alternatively, using an AI model to stratify IVF patients based on the probability of endometrial disruption revealed molecular and clinical differences between profiles. Patients were stratified into four reproductive prognosis-related profiles, p1 (n=24), p2 (n=14), c2 (n=32) and c1 (n=61). The highest pregnancy rate (PR) was associated with c1 (91%) and the highest ongoing pregnancy rate (OPR) was associated with c2 (78%), linking these profiles to good reproductive prognoses. On the other hand, p1 had the highest biochemical miscarriage rate (BMR; 43%) while p2 had the highest clinical miscarriage rate (CMR; 43%). Notably, both p1 and p2 were related to lower PR and OPR, supporting that these profiles were associated with poor prognoses. Regarding the functional characterization in the poor prognosis profiles that were linked to miscarriages, p1 was associated with an excessive immune response against the embryo during early pregnancy stages, while p2 was initially immune-tolerant but rejected the fetus in later stages due to the lack of metabolic response. Conclusion(s)This new AI-based prognostic stratification of IVF patients is promising for the clinical management of endometrial-factor infertility in precision medicine.

Research questionHow accurate is minimally invasive assessment of endometrial receptivity from uterine fluid extracellular vesicles (UF-EVs) using only 68 RNA biomarkers. Study designAssessment of endometrial receptivity by applying the beREADY computational model on transcriptomic data derived from UF-EVs during the pre-receptive (LH+2) and receptive phases (LH+7) of a natural cycle. ResultsbeREADY housekeeping gene transcript levels in UF-EV are not significantly different between LH+2 and LH+7 UF-EVs. Endometrial receptivity can be assessed from UF-EV transcriptomic data using beREADY computational model with specificity of 100% and sensitivity of 75%. ConclusionbeREADY computational model can be used on UF-EVs instead of endometrial tissue biopsy to assess endometrial receptivity. However, further development is needed to fine-tune the model to show that this model can also be used on UF-EV samples from women undergoing hormone-replacement therapy.

ObjectiveTo study the effect of a one-step warming technique on survival and clinical outcomes of vitrified-warmed blastocysts on a consecutive cohort of patients. DesignRetrospective consecutive cohort study. SubjectsThis study included 1402 transferred embryos from 989 unique patients that were treated in 3 clinics. ExposureThe exposure group included embryos warmed using a one-step warming protocol of 1M sucrose solution for 1 minute. The control group included embryos warmed using traditional, multi-step warming, where embryos were exposed to 1M sucrose for 1 min, followed by 3 min in 0.5M sucrose, and 10 mins in washing solutions. Main Outcome MeasuresThe goal of this study was to compare survival, clinical pregnancy (CPR) and ongoing pregnancy (OPR) rates between multi- and one-step warming techniques. Additionally, subgroup analyses by maternal age, embryo morphology, day of vitrification and mode of fertilization were also performed. ResultsSurvival rates were comparable across all comparisons. Pregnancy rates were comparable between multi-step and one-step groups (CPR: 42.6% vs 44.3%, p=0.78; OPR: 33.2 %vs 37.5%, p=0.21). Pregnancy probabilities between warming techniques were comparable between groups at any age point (32 - CPR: 43.0% vs 47.7%; OPR: 34.5% vs 39.5; p>0.05; 42 - CPR: 24.2% vs 19.3%; OPR: 13.5% vs 13.5%; p>0.05). Good quality embryos (G2) had a lower chance of pregnancy than top quality embryos (G1) overall, but pregnancy rates were similar between groups (G1 - CPR: 52.3% vs 54.6%; OPR: 46.0% vs 48.1%; p>0.05; G2 - CPR: 38.6% vs 40.0%; OPR: 27.8% vs 33%; p>0.05). Similarly, Day 6 embryos were less likely to achieve pregnancy than Day 5 embryos, but pregnancy rates were comparable between groups (D5 - CPR: 44.8% vs 46.5%; OPR: 35.3% vs 40.0%; p>0.05; D6 - CPR: 28.0% vs 31.2%; OPR: 18.3% vs 23.4%; p>0.05). Pregnancy rates between ICSI for male factor infertility and IVF were again comparable between groups (ICSI - CPR: 40.9% vs 38.3%; OPR: 33.7% vs 32.5%; IVF - CPR: 45.0% vs 48.0%; OPR: 37.3% vs 41.9%; p>0.05). ConclusionOne-step embryo warming provides similar survival and pregnancy outcomes compared to classical multi-step warming while decreasing the procedure time by more than 90%.

ObjectiveTo investigate the possible impact of Pfizer-BioNTechs mRNA BNT162b2 COVID-19 vaccine on womens fertility. MethodsA retrospective single-center study examining womens IVF treatment parameters and pregnancies before and after their vaccination between February and May 2021. Each woman served as a self-control before and after vaccination. Additionally, in order to neutralize the effect of the sperm on fertilization, only Intracytoplasmic Sperm Injection (ICSI) patients who were currently being treated with an ICSI cycle and had an earlier ICSI cycle available were included in the study. The study outcomes compared between the PRE and POST vaccination groups and consisted of: the IVF cycle outcomes, including the number of oocytes retrieved; the number of matured oocytes; the fertilization rate; and the number and quality of embryos at day 3. Clinical pregnancy was based on the first hCG value reported if the data were available for both cycles. ResultsA final total of 47 women were eligible for inclusion with a mean interval of 362 {+/-}368 days between the two ovum pick ups. The characteristics of their ICSI cycles before and after the vaccination were similar for all the parameters. Additionally, the number and percentage of clinical pregnancies did not significantly differ between the PRE and POST vaccination groups (n=15). ConclusionThis study is the first to evaluate the impact of the BNT162b2 vaccine on womens fertility. From our findings, the vaccine appears to have no impact on womens fertility. This study is the first step in abolishing the misinformation derived from unreliable sources and reassuring patients in order to improve compliance and promote COVID-19 eradication.

BackgroundThe synchrony between the embryo and the receptive endometrium is essential for successful implantation. Therefore, a reliable non-invasive ER prediction method is highly demanded. We aimed to establish a method that could be used to predict endometrium receptivity non-invasively and to evaluate its clinical application potential in patients undergoing IVF. MethodsThe non-invasive RNA-seq based endometrial receptivity test (nirsERT) was established by sequencing and analyzing the RNA of uterine fluid from 48 IVF patients with normal ER. Subsequently, 22 IVF patients were recruited and analyzed the correlation between the predicted results of nirsERT and pregnancy outcomes. Results87 marker genes and 3 hub genes were selected to establish the nirsERT. 10-fold cross-validation resulted in a mean accuracy of 93.0%. A small cohort retrospective observation showed that 77.8% (14/18) of IVF patients predicted with normal WOI had successful intrauterine pregnancies, while none of the 3 patients with displaced WOI had successful pregnancy. ConclusionsnirsERT is potential for a non-invasive, accurate and same cycle testing for ER in reproductive clinic. FundingFunded by the National Natural Science Foundation of China (grant no. 8187061497) and the National Key Research and Developmental Program of China (grant no. 2018YFC1004800). Clinical trial numberChiCTR-DDD-17013375.

STUDY QUESTIONWhich mechanisms of action and candidate drugs can be used to treat endometrial failure caused by molecular alterations rather than endometrial timing? SUMMARY ANSWERGenistein, pioglitazone, alprostadil, flunisolide, and tenoxicam emerged as potential therapies to treat two molecular causes of endometrial failure not originating in endometrial timing. WHAT IS KNOWN ALREADYSeveral studies have described molecular profiles of endometrial failure unrelated to endometrial timing and proposed diagnostic tools based on clinical and transcriptomic data, but effective therapeutic options remain lacking. Hence, there is a pressing need for tailored treatments to enable personalised medicine in endometrial-factor infertility. STUDY DESIGN, SIZE, DURATIONThis multicentre prospective study, conducted at 5 fertility clinics in Spain between January 2019 and August 2022, included 192 patients undergoing in vitro fertilisation with hormone replacement therapy, whose endometrial biopsies were collected during the mid-secretory phase. PARTICIPANTS/MATERIALS, SETTING, METHODSOf 291 endometrial biopsies, 192 met the quality criteria and 161 were classified according to clinical and transcriptomic data using a semi-supervised learning model for prognosis. Before classification, transcriptomic variation related to endometrial timing was corrected using our validated transcriptomic endometrial-dating model. Profiles were analysed using systems pharmacology approaches combining network analysis and reversal signature matching to identify therapeutic drugs capable of reversing molecular disruption. Candidate drugs were grouped by mechanism of action and prioritised by side-effect profile. Selected drugs were validated in endometrial cells through RT-PCR, F-actin staining, and enzyme-linked immunosorbent assays. MAIN RESULTS AND THE ROLE OF CHANCEFour transcriptomic profiles were identified using artificial intelligence models, each with distinct clinical implications. Two profiles were associated with poor prognosis: clinical miscarriage-associated (CMA, n = 27) and biochemical miscarriage-associated (BMA, n = 16). CMA was characterised by upregulation of differentiation-related genes and BMA by upregulation of immune-related genes. The 4 profiles were homogeneous in demographic and embryological parameters (age, BMI, and embryo quality), reinforcing their biological relevance. Approved drugs capable of reversing these disrupted expression patterns were identified. Both BMA and CMA were linked to abnormal decidualisation, while BMA also showed immune dysregulation. Genistein and pioglitazone promoted decidualisation in vitro, whereas alprostadil, flunisolide, and tenoxicam inhibited immune responses in endometrial cell cultures, supporting their potential therapeutic role in endometrial failure not originating in endometrial timing. LIMITATIONS, REASONS FOR CAUTIONAlthough our artificial intelligence-based stratification model revealed clinical and functional differences among profiles, it was designed for drug repurposing rather than predictive diagnosis. A larger, specifically designed study would be required to validate predictive performance and generalisability. Further clinical trials are needed to evaluate the proposed drugs as personalised treatments for this condition. WIDER IMPLICATIONS OF THE FINDINGSThis is the first application of a systems-based drug repurposing strategy in IVF to develop tailored therapeutic interventions. We propose genistein, pioglitazone, alprostadil, flunisolide, and tenoxicam as approved, safe drugs identified through an evidence-based approach that could prevent loss of good-quality embryos and miscarriage due to maternal endometrial factors. These findings, supported by functional in vitro validation, pave the way for future clinical trials advancing personalised medicine in endometrial-factor infertility. TRIAL REGISTRATION NUMBERNot applicable

Anogenital distance (AGD), the length from the anus to specific genital landmarks, is a well validated, testosterone sensitive, sexually dimorphic biomarker used in many kinds of medical and evolutionary research in diverse species of mammals, including humans. Current research into the effects of testosterone on womens reproductive health and disease is motivating increased interest in measuring female AGD. Studies quantifying female AGD typically employ a clinician, such as a gynecologist or nurse, to conduct the measurements. This methodology maximizes accuracy but imposes notable limitations on data collection. All participants submitted self-measurements online and completed a small set of questionnaires, including tests assessing spatial cognition. The accuracy of AGD self-measurements, based on agreement between self- and clinic-measurements, was moderate. Measurement accuracy was predicted by performance on the mental rotation test, such that women who performed better on this test demonstrated greater accuracy in measuring the anus to posterior fourchette distance. We describe ideas for improving the accuracy of the self-measurement technique. Self-measurement of AGD would increase the number and diversity of women represented in studies of reproductive health, reduce research expenses, and expedite research into the effects of prenatal testosterone and endocrine disruption on female health and disease.

PurposeThis study aims to establish the viability of monitoring an appropriate and safe ovarian stimulation without the use of ultrasound and serum hormone testing. MethodAs a primary marker for monitoring of the ovarian response, we used urinary estrone-3-glucuronide (E1-3G) growth rate, which was self-measured by patients daily at home, with a portable analyzer, during the stimulation. For an adequate ovarian response, an average daily rate of increase of E1-3G was estimated to be within 25 - 77%. Ovulation trigger day was determined based on the length of the menstrual cycle. The study included 24 women. Inclusion criteria were age < 41 years and AMH >1 ng/mL. A progestin-primed ovarian stimulation protocol (PPOS) with fixed doses of gonadotropins was used. ResultsThe average female age was 32,9 years ({+/-}4.4), BMI 22,7 kg/m2 ({+/-}4,3), AMH 3,7 ng/ml ({+/-}2,6), stimulation days 10,6 ({+/-}1,1), collected oocytes 12,5 ({+/-}8,5), MII oocytes 10,6 ({+/-}7,8), fertilization rate 83,6% ({+/-}22,5), blastocyst 66,4% ({+/-}28,6), good quality blastocysts 31,6% ({+/-}16,9). Absence of oocyte aspiration was found in one of the cases. There were no cases of OHSS and ovarian stimulation cancellation. ConclusionThis is the first pilot study to successfully apply a new markers for ovarian stimulation monitoring.

ImportanceLimited knowledge exists on the effects of SARS-CoV-2 infection after embryo transfer, despite an increasing number of studies exploring the impact of previous SARS-CoV-2 infection on IVF outcomes. ObjectiveThis prospective cohort study aimed to assess the influence of SARS-CoV-2 infection at various time stages after embryo transfer on pregnancy outcomes in patients undergoing conventional in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI) treatment. DesignThe study was conducted at a single public IVF center in China. SettingThis was a population-based prospective cohort study. ParticipantsFemale patients aged 20 to 39 years, with a body mass index (BMI) between 18 and 30 kg/m2, undergoing IVF/ICSI treatment, were enrolled from September 2022 to December 2022, with follow-up until March 2023. ExposureThe pregnancy outcome of patients was compared between those SARS-CoV-2-infected after embryo transfer and those noninfected during the follow-up period. Main Outcomes and MeasuresThe pregnancy outcomes included biochemical pregnancy rate, implantation rate, clinical pregnancy rate, and early miscarriage rate. ResultsA total of 857 female patients undergoing IVF/ICSI treatment were included in the analysis. We observed the incidence of SARS-CoV-2 infection within 10 weeks after embryo transfer. The biochemical pregnancy rate and implantation rate were lower in the infected group than the uninfected group (58.1% vs 65.9%; 36.6% vs 44.0%, respectively), but no statistically significant. Although, the clinical pregnancy rate was significant lower in the infection group when compared with the uninfected group (49.1%vs 58.2%, p < 0.05), after adjustment for confounders, this increased risk was no longer significant between the two groups (adjusted OR, 0.736, 95% CI, 0.518-1.046). With continued follow-up, a slightly higher risk of early miscarriage in the infected group compared to the uninfected group (9.3% vs 8.8%), but it was not significant (adjusted OR, 0.907, 95% CI, 0.414-1.986). Conclusions and RelevanceThe studys findings suggested that SARS-CoV-2 infection within 10 weeks after embryo transfer may have not significantly affect pregnancy outcomes. This evidence allays concerns and provides valuable insights for assisted reproduction practices. Key pointsO_ST_ABSQuestionC_ST_ABSDid the infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after embryo transfer affect pregnancy outcomes? FindingsIn this prospective cohort study involving 857 patients, we made a pioneering discovery that SARS-CoV-2 infection following embryo transfer did not exhibit adverse impact on the biochemical pregnancy rate, embryo implantation rate, clinical pregnancy rate, and early miscarriage rate. MeaningThe evidence from this study alleviates existing concerns and offers new insights into the actual risk of SARS-CoV-2 infection after embryo transfer in assisted reproduction.

ObjectiveTo evaluate how minimal controlled ovarian stimulation (COS) for in vitro maturation (IVM) affects subjects oocyte retrieval experiences compared to conventional COS, considering side effects DesignRetrospective Survey Study SettingClinical in vitro fertilization (IVF) treatment centers in Spain and the United States. SubjectsData were collected from subjects undergoing minimal COS (n=110; 600-800 IU FSH) for IVM and conventional COS for egg donation (n=48; 2000-3000 IU FSH) from April 2022 to November 2023. In the same period, a pairwise comparison of subjects (n=13) undergoing both minimal COS for IVM and conventional COS for oocyte cryopreservation was conducted. Intervention/ExposureMinimal and conventional controlled ovarian stimulation. Main Outcome MeasuresThe most common side effects suffered during ovarian stimulation and after OPU, satisfaction level, and the likelihood of recommending or repeating minimal or conventional COS. Statistical analysis included Mann Whitney, Wilcoxon, Chi-square, and McNemar tests, with a significance level set at p<0.05. ResultsDuring minimal COS, most subjects did not experience breast swelling (86%), pelvic or abdominal pain (76%), nausea or vomiting (96%), and bleeding (96%). After oocyte pick-up, the majority (75%) reported no pelvic or abdominal pain. The most common side effect was abdominal swelling (52%). Compared to conventional COS cycles, minimal COS subjects reported significantly less post-retrieval pain, with 33% experiencing no pain (vs. 6%; p=0.0011) and with a reduced severe level of pain (5% vs.19%; p=0.0097), leading to fewer subjects requiring pain medication (25% vs. 54%; p=0.0003). Additionally, 85% of women were very satisfied with minimal stimulation and would recommend or repeat the treatment. In the comparison in which each donor underwent both minimal and conventional COS treatments, women indicated more side effects with the conventional stimulation, presenting a significantly overall higher level of pain (p=0.0078). ConclusionReducing the hormonal dose for ovarian stimulation has a beneficial effect on subjects, suggesting the combination of minimal COS with IVM techniques is a well-tolerated alternative for women who cannot or do not wish to undergo conventional controlled ovarian hyperstimulation.

Ovarian tissue cryopreservation and subsequent autologous transplantation has allowed resumption of endocrine function as well as fertility in certain populations. However, graft function is short-lived due to ischemia and aberrant follicular activation post-transplantation. While many studies have focused on gene expression, we wanted to determine whether cryopreservation itself had a deleterious effect on regulatory elements that might influence transcriptional integrity and graft performance. In this study, we used Omni-ATAC to assess genome-wide chromatin accessibility in primary human follicles before and after cryopreservation. Omni-ATAC from fresh ovarian follicles identified active regulatory elements expected to be functional in oocytes and granulosa cells, and gene ontology was consistent with RNA translation/processing and DNA repair. While promoter accessibility was largely maintained in cryopreserved ovarian follicles, we observed a widespread increase in the number of accessible enhancers. Transcription factor motif analysis and gene ontology suggested that this dysregulation was focused around the epithelial-mesenchymal transition. Indeed, transcription factor binding was noted in major pathways involved in this transition: TGF-{beta} and Wnt signaling. Overall, our work provides the first genomic analysis of active regulatory elements in matched fresh and cryopreserved ovarian follicles as they undergo the process of ovarian tissue cryopreservation. Our data suggest that the process of cryopreservation activates an epithelial-mesenchymal transition state, which may lead to graft burn-out post-transplantation. Optimizing this technique in relation to this transition may therefore be an important step towards improving graft longevity and patient outcomes in fertility preservation. Summary sentenceCryopreservation of ovarian cortical tissue results in activation of differentiation and EMT pathways in follicles, which may explain graft burnout after autotransplantation.

IntroductionPhysiological oocyte activation requires a synergy between the oocyte and sperm to release calcium (Ca2+) through oscillations. The absence of such synergy between the oocyte and sperm leads to a negative impact on oocyte activation. Studies have shown that Artificial oocyte activation (AOA) is helpful in cases with failed or low fertilization rates. Studies present mixed opinions about increasing blastocyst rate. MethodsA retrospective cohort single-center study was performed between January 2018 and October 2023, including 54 couples with suboptimal blastocyst development. The study compared intracytoplasmic sperm injection (ICSI) AOA cycles with previous conventional ICSI cycles and conventional ICSI without AOA cycles with previous conventional ICSI cycles in couples with failed or low blastocyst rates (< 30%) in the original ICSI cycle. ResultsWe compared 22 AOA cycles to previous conventional ICSI cycles in the same patients and 32 conventional ICSI cycles without AOA to previous conventional ICSI cycles in the same patients. After AOA, the blastocyst rate was not significantly higher than the control group (48% vs 29% p=0.19). Conversely, the blastocyst rate was significantly higher in the conventional ICSI without AOA cycles than in the control group (48% vs 24% p=0.04). The fertilization rate was not statistically significant between the first and second cycles in both groups. ConclusionThe literature still lacks strong evidence for AOA overcoming impaired embryonic development. Therefore, AOA remains reserved for couples with a failed or low fertilization history to improve fertilization results. Optimal laboratory conditions and ovarian stimulation modifications without AOA may improve blastocyst rates.

STUDY QUESTIONCan a large-scale genome-wide association study (GWAS) meta-analysis identify the genomic risk loci and associated candidate genes for female genital tract (FGT) polyps, provide insights into the mechanism underlying their development, and inform potential overlap with other traits, including endometrial cancer? SUMMARY ANSWERGWAS meta-analysis of FGT polyps highlighted the potentially shared mechanisms between polyp development and cancerous processes. WHAT IS KNOWN ALREADYSmall-scale candidate gene studies have focused on biological processes such as estrogen stimulation and inflammation to clarify the biology behind FGT polyps. However, the exact mechanism for the development of polyps is still elusive. At the same time, a genome-wide approach, which has become the gold standard in complex disease genetics, has never been used to uncover the genetics of the FGT polyps. STUDY DESIGN, SIZE, DURATIONWe performed a genome wide association study (GWAS) meta-analysis including a total of 25,100 women with FGT polyps (International Classification of Disease, ICD-10 diagnosis code N84) and 207,193 female controls (without N84 code) of European ancestry from the FinnGen study (11,092 cases and 94,394 controls) and the Estonian Biobank (EstBB, 14,008 cases and 112,799 controls). PARTICIPANTS/MATERIALS, SETTING, METHODSA meta-analysis and functional annotation of GWAS signals were performed to identify and prioritise genes in associated loci. To determine associations with other phenotypes, we performed a look-up of associated variants across multiple traits and health conditions, a genetic correlation analysis, and a phenome-wide association study (PheWAS) with ICD10 diagnosis codes. MAIN RESULTS AND THE ROLE OF CHANCEOur GWAS meta-analysis revealed ten significant (P < 5 x 10-8) genomic risk loci. Two signals, rs2277339 (P = 7.6 x 10-10) and rs1265005 (P = 1.1 x 10-9) (in linkage disequilibrium (LD) with rs805698 r2 = 0.75), are exonic missense variants in PRIM1, and COL17A1 genes, respectively. Based on the literature, these genes may play a role in cellular proliferation. Several of the identified genomic loci had previously been linked to endometrial cancer and/or uterine fibroids. Thus, highlighting the potentially shared mechanisms underlying tissue overgrowth and cancerous processes, which may be relevant to the development of polyps. Genetic correlation analysis revealed a negative correlation between sex hormone-binding globulin (SHBG) and the risk of FGT polyps (rg = -0,21, se = 0.04, P = 2.9 x 10-6), and on the phenotypic level (PheWAS), the strongest associations were observed with endometriosis, leiomyoma of the uterus and excessive, frequent and irregular menstruation. LARGE SCALE DATAThe complete GWAS summary statistics will be made available after publication through the GWAS Catalogue (https://www.ebi.ac.uk/gwas/). LIMITATIONS, REASONS FOR CAUTIONIn this study, we focused broadly on polyps of FGT and did not differentiate between the polyp subtypes. The prevalence of FGT polyps led us to assume that most women included in the study had endometrial polyps. Further study on the expression profile of FGT polyps could complement the GWAS study to substantiate the functional importance of the identified variants. WIDER IMPLICATIONS OF THE FINDINGSThe study findings have the potential to significantly enhance our understanding of the genetic mechanisms involved, paving the way for future functional follow-up, which in turn could improve the diagnosis, risk assessment, and targeted treatment options, since surgery is the only line of treatment available for diagnosed polyps. TRIAL REGISTRATION NUMBERNot applicable

AimTo review the pathological findings of uterine niches in women presenting with infertility and abnormal uterine bleeding. MethodsThe Medline, Embase, and Cochrane Central databases were searched until 1 May 2025. We included cohorts, case-controls, and case series. The risk of bias was evaluated with ROBINS-I, and the certainty of evidence was presented according to GRADE. ResultsWe included fourteen studies (637 women). Chronic inflammation was observed in 54% (95% CI 25 to 81%; 5 studies, 280 women; I2 = 94.3%); fibrosis in 83% (95% CI 51 to 96%; 6 studies, 266 women; I2 = 92.1%); endometrial defects in 90% (95% CI 75 to 96%; 4 studies, 177 women; I2 = 64.6%); ectopic endometrium in 26% (95% CI 18 to 36%; 9 studies, 411 women; I2 = 74.2%); and vascular remodeling in 81% (95% CI 75 to 86%; 6 studies, 205 women; I2 = 0.0%). There was an increased risk of endometrial defects in women with niches compared to those with prior cesarean deliveries (RR 2.13, 95% CI 1.27 to 3.55; 2 studies, 124 women; I2 = 0.0%), similarly for ectopic endometrium (RR 2.86, 95% CI 1.03 to 7.96; 2 studies, 97 women; I2 = 0.0%). Additionally, niches exhibited a pro-inflammatory phenotype, characterized by elevated expression of CD138 and TNF-. ConclusionsThe observed pathological features suggest an underlying process driven by the interplay of chronic inflammation, altered immune cell recruitment, fibrosis, and vascular remodeling within the regenerating endometrium. Registration numberCRD420251049667.

A genetic etiology accounts for unexplained primary ovarian insufficiency (POI; amenorrhea with an elevated FSH level). Subjects with POI (n=291) and controls recruited for health in old age or 1000 Genomes (n=233) underwent whole exome or whole genome sequencing. Data were analyzed using a rare variant scoring method and a Bayes factor-based framework for identifying genes harboring pathogenic variants. Candidate heterozygous variants were identified in known genes and genes with functional evidence. Gene sets with increased burden of deleterious alleles included the categories transcription and translation, DNA damage and repair, meiosis and cell division. Variants were found in novel genes from the enhanced categories. Functional evidence supported 7 new risk genes for POI (USP36, VCP, WDR33, PIWIL3, NPM2, LLGL1 and BOD1L1). Aggregating clinical data and genetic risk with a categorical approach may expand the genetic architecture of heterozygous rare gene variants causing risk for POI.

BackgroundIn vitro fertilization (IVF) has revolutionized reproductive medicine; however, IVF-conceived offspring exhibit a higher risk of various long-term health issues. The underlying mechanisms remain unclear. Long Interspersed Nuclear Element-1 (L1), a mobile genetic element sensitive to environmental stress, is a potential mediator. We hypothesized that the IVF procedure acts as an embryonic stress, altering L1 retrotransposition and contributing to genomic instability associated with disease risk. MethodsWhole blood from 33 IVF and 42 naturally conceived (NC) offspring were collected for deep sequencing. We quantified L1 genomic content and mapped novel L1 insertions and deletions with Bowtie2 and MELT, and further compared their frequencies and genomic distributions between the two groups. Gene-disease association analysis was performed on genes within 500kb of differential L1 sites. ResultsThe overall L1 content was significantly higher in IVF offspring compared to NC controls (P<0.05), a finding robustly confirmed in three sibling pairs from the same parents where the IVF children had higher L1 content than their NC siblings. We identified 11 specific genomic loci with significantly different L1 insertion frequencies and 14 loci with different deletion frequencies between IVF and NC offspring. Notably, these differential sites were often located near genes significantly associated with metabolic, cardiovascular, neuropsychiatric, and neoplastic diseases, conditions previously linked to IVF conception. ConclusionOur findings demonstrate that IVF conception is associated with increased L1 content and altered genomic distribution of L1 elements in offspring. The disease-related genes near these aberrant L1 sites provide a plausible genomic link between IVF-associated embryonic stress and the increased risk of specific diseases in the IVF population. This study offers novel insights into the molecular safety of ART.

PCOS is the most common hormonal disorder and cause of infertility in females of reproductive age. The symptoms and their severity vary strongly between particular cases. PCOS is correlated with hormonal, environmental and genetic factors. Complex interactions between genetics and hormonal levels is important to understand the hormonal 31 abnormality and to assess the chance of pregnancy in women with PCOS. The research was conducted on patients in the age of 27+/-5 years treated in the 33 Gynecology and Oncology Clinic of CMUJ. The research group - PCOS patients (P) n=62. The control group - (C) n=45. The venous blood was collected in volume of 2 ml centrifuged for 15 min at 1400 rpm. Serum was aspirated to 1.5 ml Eppendorf tubes. The ELISA method was used. The statistical analysis revealed significant differences in the level of selected factors 38 between the two groups at p <0.01. FSH [IU/ml]: P 5,10 ({+/-}1,64) vs K 8,96 ({+/-}6,15) LH [ IU/ml]: P 8,59 ({+/-}6,79) vs K 11,0 ({+/-}6,15) AMH [ng/ml]: P 4,06 ({+/-}2,43) vs K 1,47 ({+/-}2,14). AMH levels in the PCOS group did not show a significant difference in correlation with age. Obese and overweight women in both 42 groups had significantly different levels of AMH compared with normal-weight women. Furthermore, AMH levels were positively correlated with the age of the first period in the PCOS. The studies indicate a high use of the hormones like FSH and AMH in the diagnosis and assessment of ovarian reserve in women with PCOS.

This study investigates the impact of progesterone resistance on endometrial receptivity and evaluates the efficacy of pituitary downregulation combined with hormone replacement therapy (HRT) in improving pregnancy outcomes following frozen embryo transfer (FET). A retrospective analysis was conducted on 147 patients with recurrent implantation failure (RIF) who underwent secretory-phase endometrial biopsy and subsequent FET treatments at the Reproductive Center of the First Affiliated Hospital of Guangxi Medical University between April 2019 and May 2022. Based on biopsy results and endometrial preparations, patients were categorized into four groups: secretory phase + non-downregulated protocol group (n=29), secretory phase + GnRH-a + HRT Protocol group (n=20), proliferative phase + non-downregulated protocol group (n=59), proliferative Phase + GnRH-a + HRT Protocol group (n=39). Endometrial preparation regimens and pregnancy outcomes during the first FET cycle after biopsy were compared. The results showed that there was no statistical difference in the outcome of assisted pregnancy between the different endometrial preparation protocols in the four groups. These findings suggest that the prioritization of down-regulation protocols may not be essential for FET in patients with RIF, even when endometrial biopsy during the implantation window reveals proliferative-phase characteristics.