Conserved genes regulating human sex differentiation, gametogenesis and fertilization.

The study of the functional genome in mice and humans has been instrumental for describing the conserved molecular mechanisms regulating human reproductive biology, and for defining the etiologies of monogenic fertility disorders. Infertility is a reproductive disorder that includes various conditions affecting a couple's ability to achieve a healthy pregnancy. Recent advances in next-generation sequencing and CRISPR/Cas-mediated genome editing technologies have facilitated the identification and characterization of genes and mechanisms that, if affected, lead to infertility. We report established genes that regulate conserved functions in fundamental reproductive processes (e.g., sex determination, gametogenesis, and fertilization). We only cover genes the deletion of which yields comparable fertility phenotypes in both rodents and humans. In the case of newly-discovered genes, we report the studies demonstrating shared cellular and fertility phenotypes resulting from loss-of-function mutations in both species. Finally, we introduce new model systems for the study of human reproductive biology and highlight the importance of studying human consanguineous populations to discover novel monogenic causes of infertility. The rapid and continuous screening and identification of putative genetic defects coupled with an efficient functional characterization in animal models can reveal novel mechanisms of gene function in human reproductive tissues.

The reproductive potential of vitrified-warmed euploid embryos declines following repeated uterine transfers.

BACKGROUND: Recurrent implantation failure (RIF) represents a vague clinical condition with an unclear diagnostic challenge that lacks solid scientific underpinning. Although euploid embryos have demonstrated consistent implantation capabilities across various age groups, a unanimous agreement regarding the advantages of preimplantation genetic testing for aneuploidy (PGT-A) in managing RIF is absent. The ongoing discussion about whether chromosomal aneuploidy in embryos significantly contributes to recurrent implantation failure remains unsettled. Despite active discussions in recent times, a universally accepted characterization of recurrent implantation failure remains elusive. We aimed in this study to measure the reproductive performance of vitrified-warmed euploid embryos transferred to the uterus in successive cycles. METHODS: This observational cohort study included women (n = 387) with an anatomically normal uterus who underwent oocyte retrieval for PGT-A treatment with at least one biopsied blastocyst, between January 2017 and December 2021 at a university-affiliated public fertility center. The procedures involved in this study included ICSI, blastocyst culture, trophectoderm biopsy and comprehensive 24-chromosome analysis of preimplantation embryos using Next Generation Sequencing (NGS). Women, who failed a vitrified-warmed euploid embryo transfer, had successive blastocyst transfer cycles (FET) for a total of three using remaining cryopreserved euploid blastocysts from the same oocyte retrieval cycle. The primary endpoints were sustained implantation rate (SIR) and live birth rate (LBR) per vitrified-warmed single euploid embryo. The secondary endpoints were mean euploidy rate (m-ER) per cohort of biopsied blastocysts from each patient, as well as pregnancy and miscarriage rates. RESULTS: The mean age of the patient population was 33.4 years (95% CI 32.8-33.9). A total of 1,641 embryos derived from the first oocyte retrieval cycle were biopsied and screened. We found no associations between the m-ER and the number of previous failed IVF cycles among different ranges of maternal age at oocyte retrieval (P = 0.45). Pairwise comparisons showed a significant decrease in the sustained implantation rate (44.7% vs. 30%; P = 0.01) and the livebirth rate per single euploid blastocyst (37.1% vs. 25%; P = 0.02) between the 1st and 3rd FET. The cumulative SIR and LBR after up to three successive single embryo transfers were 77.1% and 68.8%, respectively. We found that the live birth rate of the first vitrified-warmed euploid blastocyst transferred decreased significantly with the increasing number of previously failed IVF attempts by categories (45.3% vs. 35.8% vs. 27.6%; P = 0.04). A comparable decrease in sustained implantation rate was also observed but did not reach statistical significance (50% vs. 44.2 vs. 37.9%; P = NS). Using a logistic regression model, we confirmed the presence of a negative association between the number of previous IVF failed attempts and the live birth rate per embryo transfer cycle (OR = 0.76; 95% CI 0.62-0.94; P = 0.01). CONCLUSIONS: These findings are vital for enhancing patient counseling and refining management strategies for individuals facing recurrent implantation failure. By tailoring interventions based on age and ovarian reserve, healthcare professionals can offer more personalized guidance, potentially improving the overall success rates and patient experiences in fertility treatments. TRIAL REGISTRATION NUMBER: N/A.

The Effects of Long-Term Dienogest Therapy on In Vitro Fertilization Outcomes in Women with Endometriosis: A Systematic Review and Meta-Analysis.

OBJECTIVES: Assessing dienogest's efficacy in endometriosis patients undergoing in vitro fertilization (IVF). DATA SOURCES: Systematic search in databases (PubMed, MEDLINE, Embase, Web of Science, Cochrane CENTRAL, Google Scholar) until 1 October 2022. STUDY SELECTIONS: Randomized trials and observational studies comparing extended dienogest pre-treatment, no pre-treatment, or gonadotropin-releasing hormone (GnRH) agonist pre-treatment in endometriosis-linked IVF. OUTCOME MEASURES: live birth, clinical pregnancy rates, oocytes collected, miscarriage rate, gonadotropin consumption. DATA EXTRACTIONS AND SYNTHESES: Two authors independently assessed eligibility. Dichotomous variables were analyzed via a random-effect model and Mantel-Haenszel method to calculate weighted estimates and 95% confidence intervals (CI). I2 statistic gauged study heterogeneity; GRADE criteria evaluated evidence quality. CONCLUSIONS: Out of 191 publications, five studies with 723 participants were included. Uncertainty persists on whether prolonged dienogest affects live birth (RR 1.42, 95% CI 0.29 to 6.84; 3 studies, n = 289; I2 86%) and clinical pregnancy rates (RR 1.33, 95% CI 0.31 to 5.65; 3 studies, n = 289; I2 86%) compared to conventional IVF. Moreover, uncertainty remains regarding intervention impact on live birth (RR 1.46, 95% CI 0.63 to 3.37; 1 study, n = 34) and clinical pregnancy rates (RR 1.32, 95% CI 0.78 to 2.23; 3 studies, n = 288; I2 0%) versus long-term GnRH agonist therapy before IVF. Given limited data and very low evidence quality, doubts arise about the benefits of long-term dienogest pre-treatment before conventional IVF in endometriosis patients.

Clostridium perfringens Bacteraemia following Normal Vaginal Delivery.

Clostridial uterine infections and bacteraemia are of a rare occurrence, especially in the absence of risk factors. However, when encountered, they can carry significant morbidity and mortality rates. We present a rare case of C. perfringens bacteraemia in the immediate postpartum period of a noncomplicated vaginal delivery. Prompt diagnosis and early initiation of treatment were imperative for ensuring a safe recovery of the patient. Despite the fact that bacteraemia caused by C. perfringens is an infrequent event in the uneventful postpartum phase, maintaining vigilance for the potential occurrence of such an event allows for early detection and timely administration of antibiotics and resuscitative measures.