Association between proliferative-to-secretory endometrial compaction and pregnancy outcomes after embryo transfer: a systematic review and meta-analysis.

STUDY QUESTION: Does the change in endometrial thickness (EMT) from the end of the follicular/estrogen phase to the day of embryo transfer (ET) determine subsequent pregnancy outcomes? SUMMARY ANSWER: Endometrial compaction from the late-proliferative to secretory phase is not associated with live birth rate (LBR) and other pregnancy outcomes. WHAT IS KNOWN ALREADY: Endometrial compaction has been suggested to be indicative of endometrial responsiveness to progesterone, and its association with ET outcome has been investigated but is controversial. STUDY DESIGN, SIZE, DURATION: A systematic review with meta-analysis was carried out. PubMed, EMBASE, and Web of Science were searched to identify relevant studies from inception to 18 November 2022. The reference lists of included studies were also manually screened for any additional publications. PARTICIPANTS/MATERIALS, SETTING, METHODS: Cohort studies comparing ET pregnancy outcomes between patients with and without endometrial compaction were included. A review of the studies for inclusion, data extraction, and quality assessment was performed by two independent reviewers. The effect size was synthesized as odds ratio (OR) with 95% CI using a random-effects model. Heterogeneity and publication bias were assessed by the I2 statistic and Egger's test, respectively. The primary outcome was LBR. Secondary outcomes included biochemical pregnancy rate (BPR), clinical pregnancy rate (CPR), miscarriage rate (MR), ongoing pregnancy rate (OPR), and ectopic pregnancy rate (EPR). MAIN RESULTS AND THE ROLE OF CHANCE: Seventeen cohort studies involving 18 973 ET cycles fulfilled the eligibility criteria. The pooled results revealed that there were no significant differences between endometrial compaction and non-compaction groups in LBR (crude OR (cOR) = 0.95, 95% CI 0.87-1.04; I2 = 0%; adjusted OR (aOR) = 1.02, 95% CI 0.87-1.19, I2 = 79%), BPR (cOR = 0.93, 95% CI 0.81-1.06; I2 = 0%; aOR = 0.88, 95% CI 0.75-1.03, I2 = 0%), CPR (cOR = 0.98, 95% CI 0.81-1.18; I2 = 70%; aOR = 0.86, 95% CI 0.72-1.02, I2 = 13%), MR (cOR = 1.09, 95% CI 0.90-1.32; I2 = 0%; aOR = 0.91, 95% CI 0.64-1.31; I2 = 0%), and EPR (cOR = 0.70, 95% CI 0.31-1.61; I2 = 61%). The OPR was marginally higher in crude analysis (cOR = 1.48, 95% CI 1.01-2.16; I2 = 81%) among women with compacted endometrium, but was not evident in adjusted results (aOR = 1.36, 95% CI 0.86-2.14; I2 = 84%). Consistently, the pooled estimate of LBR remained comparable in further subgroup and sensitivity analyses according to the degree of compaction (0%, 5%, 10%, 15%, or 20%), type of ET (fresh, frozen, or euploid only), and endometrial preparation protocol (natural or artificial). No publication bias was observed based on Egger's test. LIMITATIONS, REASONS FOR CAUTION: Although the number of included studies is sufficient, data on certain measures, such as EPR, are limited. The inherent bias and residual confounding were also inevitable owing to the observational study design. Furthermore, inconsistent definitions of pregnancy outcomes may affect the accuracy of our pooled analysis. WIDER IMPLICATIONS OF THE FINDINGS: Given the lack of prognostic value, assessing endometrial compaction or repeated EMT measurement on the day of ET may not be necessary or warranted. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by Natural Science Foundation of Jiangxi Province (20224BAB216025), National Natural Science Foundation of China (82260315), and Central Funds Guiding the Local Science and Technology Development (20221ZDG020071). The authors have no conflicts of interest to declare. REGISTRATION NUMBER: CRD42022384539 (PROSPERO).

Dietary regulation of intestinal stem cells in health and disease.

Diet is a critical regulator for physiological metabolism and tissue homeostasis, with a close relation to health and disease. As an important organ for digestion and absorption, the intestine comes into direct contact with many dietary components. The rapid renewal of its mucosal epithelium depends on the continuous proliferation and differentiation of intestinal stem cells (ISCs). The function and metabolism of ISCs can be controlled by a variety of dietary patterns including calorie restriction, fasting, high-fat, ketogenic, and high-sugar diets, as well as different nutrients including vitamins, amino acids, dietary fibre, and probiotics. Therefore, dietary interventions targeting ISCs may make it possible to prevent and treat intestinal disorders such as colon cancer, inflammatory bowel disease, and radiation enteritis. This review summarised recent research on the role and mechanism of diet in regulating ISCs, and discussed the potential of dietary modulation for intestinal diseases.

Dysregulation of ferroptosis-related genes in granulosa cells associates with impaired oocyte quality in polycystic ovary syndrome.

Background: Poor oocyte quality remains one of the major challenges for polycystic ovary syndrome (PCOS) patients during in vitro fertilization (IVF) treatment. Granulosa cells (GCs) in PCOS display altered functions and could cause an unfavorable microenvironment for oocyte growth and maturation. Ferroptosis is a new form of programmed cell death, but its role in PCOS has been largely unclarified. Methods: Ferroptosis-related differentially expressed genes (DEGs) of GCs in women with PCOS were identified by bioinformatic analyses of GSE155489 and GSE168404 datasets. Functional enrichment analyses were conducted using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Core ferroptosis-related genes were further screened by random forest, and evaluated for diagnostic value by receiver operating characteristic curve analyses. Gene expression was validated by real-time quantitative polymerase chain reaction of collected GC samples, and analyzed for association with oocyte quality. In addition, gene regulatory network was constructed based on predicted RNA interactions and transcription factors, while potential therapeutic compounds were screened through molecular docking with crystallographic protein structures. Results: A total of 14 ferroptosis-related DEGs were identified. These DEGs were mainly enriched in reactive oxygen species metabolic process, mitochondrial outer membrane, antioxidant activity as well as ferroptosis and adipocytokine signaling pathways. Eight core ferroptosis-related genes (ATF3, BNIP3, DDIT4, LPIN1, NOS2, NQO1, SLC2A1 and SLC2A6) were further selected in random forest model, which showed high diagnostic performance for PCOS. Seven of them were validated in GC samples, and five were found to be significantly and positively correlated with one or more oocyte quality parameters in PCOS patients, including oocyte retrieval rate, mature oocyte rate, normal fertilization rate, and good-quality embryo rate. Gene regulatory network revealed JUN and HMGA1 as two important transcription factors, while dicoumarol and flavin adenine dinucleotide were predicted as small molecules with therapeutic potential. Conclusions: This is the first comprehensive report to study the differential expression of ferroptosis-related genes in GCs of PCOS and their clinical relevance with oocyte quality. Our findings could provide novel insights on the potential role of GC ferroptosis in PCOS pathogenesis, diagnosis, and targeted treatment.

WTAP gene variants and susceptibility to ovarian endometriosis in a Chinese population.

Background: Endometriosis is a common chronic gynecologic disorder with a significant negative impact on women's health. Wilms tumor 1-associated protein (WTAP) is a vital component of the RNA methyltransferase complex for N6-methyladenosine modification and plays a critical role in various human diseases. However, whether single nucleotide polymorphisms (SNPs) of the WTAP gene predispose to endometriosis risk remains to be investigated. Methods: We genotyped three WTAP polymorphisms in 473 ovarian endometriosis patients and 459 control participants using the Agena Bioscience MassArray iPLEX platform. The logistic regression models were utilized to assess the associations between WTAP SNPs and the risk of ovarian endometriosis. Results: In the single-locus analyses, we found that the rs1853259 G variant genotypes significantly increased, while the rs7766006 T variant genotypes significantly decreased the association with ovarian endometriosis risk. Combined analysis indicated that individuals with two unfavorable genotypes showed significantly higher ovarian endometriosis risk (adjusted OR = 1.71 [1.23-2.37], p = 0.001) than those with zero risk genotypes. In the stratified analysis, the risk effect of the rs1853259 AG/GG and rs7766006 GG genotypes was evident in subgroups of age ≤30, gravidity≤1, parity≤1, rASRM stage I, and the rs7766006 GG genotype was associated with worse risk (adjusted OR = 1.64 [1.08-2.48], p = 0.021) in the patients with rASRM stage II + III + IV. The haplotype analysis indicated that individuals with GGG haplotypes had a higher risk of ovarian endometriosis than wild-type AGG haplotype carriers. Moreover, false positive report probability and Bayesian false discovery probability analysis validated the reliability of the significant results. The quantitative expression trait loci analysis revealed that rs1853259 and rs7766006 were correlated with the expression levels of WTAP. Conclusion: Our findings demonstrated that WTAP polymorphisms were associated with susceptibility to ovarian endometriosis among Chinese women.

Impact of inactivated COVID-19 vaccination on female ovarian reserve: a propensity score-matched retrospective cohort study.

Purpose: To explore the impact of inactivated COVID-19 vaccination on ovarian reserve as assessed by serum anti-Müllerian hormone (AMH) concentration. Methods: A total of 3160 women were included in this single-center retrospective cohort study between June 2021 and October 2022. Vaccination information were collected from official immunization records available in personal mobile apps. Serum AMH was qualified by electrochemiluminescence immunoassay and compared with previous measurement data within three years. Women were categorized to the vaccinated group if they received two doses of inactivated COVID-19 vaccines (Sinopharm or Sinovac) between AMH tests (n = 488), and to the control group if not vaccinated (n = 2672). Propensity score matching and multivariate linear regression were performed to control for potential confounders. The main outcome measures were the numeric AMH change and percentage AMH change between the two tests. Results: There were 474 women left in each group after matching all baseline characteristics. The mean interval from the first to second AMH measurement was 508.0 ± 250.2 and 507.5 ± 253.6 days for vaccinated and unvaccinated women, respectively (P = 0.680). Both groups had a significant AMH decrease in the second test compared with the first test (P = 0.001). However, the second AMH level remained comparable between groups (3.26 ± 2.80 vs. 3.24 ± 2.61 ng/mL, P = 0.757). Similarly, no significant differences were observed in numerical (-0.14 ± 1.32 vs. -0.20 ± 1.56 ng/mL, P = 0.945) and percentage (2.33 ± 58.65 vs. 0.35 ± 48.42%, P = 0.777) AMH changes. The results were consistent in sub-analyses for women aged <35 and ≥35 years. There were also no significant differences when vaccinated women were divided according to the time interval after vaccination: ≤30, 31-60, 61-90, and ≥91 days. Conclusion: Our study provides the first evidence that inactivated COVID-19 vaccination has no measurable detrimental effect on ovarian reserve, regardless of female age and vaccination interval. This reassuring finding adds to the safety evidence of COVID-19 vaccine in fertility, and should be useful to promote vaccine acceptance. Multicenter prospective cohort studies are needed to validate our conclusion.