Gynecological Cancers and Microbiota Dynamics: Insights into Pathogenesis and Therapy.

In recent years, the relationship between the microbiota and various aspects of health has become a focal point of scientific investigation. Although the most studied microbiota concern the gastrointestinal tract, recently, the interest has also been extended to other body districts. Female genital tract dysbiosis and its possible impact on pathologies such as endometriosis, polycystic ovary syndrome (PCOS), pelvic inflammatory disease (PID), and gynecological cancers have been unveiled. The incursion of pathogenic microbes alters the ecological equilibrium of the vagina, triggering inflammation and compromising immune defense, potentially fostering an environment conducive to cancer development. The most common types of gynecological cancer include cervical, endometrial, and ovarian cancer, which occur in women of any age but especially in postmenopausal women. Several studies highlighted that a low presence of lactobacilli at the vaginal level, and consequently, in related areas (such as the endometrium and ovary), correlates with a higher risk of gynecological pathology and likely contributes to increased incidence and worse prognosis of gynecological cancers. The complex interplay between microbial communities and the development, progression, and treatment of gynecologic malignancies is a burgeoning field not yet fully understood. The intricate crosstalk between the gut microbiota and systemic inflammation introduces a new dimension to our understanding of gynecologic cancers. The objective of this review is to focus attention on the association between vaginal microbiota and gynecological malignancies and provide detailed knowledge for future diagnostic and therapeutic strategies.

An annotated human blastocyst dataset to benchmark deep learning architectures for in vitro fertilization.

Medical Assisted Reproduction proved its efficacy to treat the vast majority forms of infertility. One of the key procedures in this treatment is the selection and transfer of the embryo with the highest developmental potential. To assess this potential, clinical embryologists routinely work with static images (morphological assessment) or short video sequences (time-lapse annotation). Recently, Artificial Intelligence models were utilized to support the embryo selection procedure. Even though they have proven their great potential in different in vitro fertilization settings, there is still considerable room for improvement. To support the advancement of algorithms in this research field, we built a dataset consisting of static blastocyst images and additional annotations. As such, Gardner criteria annotations, depicting a morphological blastocyst rating scheme, and collected clinical parameters are provided. The presented dataset is intended to be used to train deep learning models on static morphological images to predict Gardner's criteria and clinical outcomes such as live birth. A benchmark of human expert's performance in annotating Gardner criteria is provided.

ICSI for non-male factor infertility: time to reappraise IVF?

Intracytoplasmic sperm injection (ICSI) was initially introduced to overcome problems due of severe male factor infertility not being solved with conventional in-vitro fertilization (cIVF). However, recent years have witnessed an increasing use of ICSI by most assisted reproductive technique laboratories for non-male factor indications. Examples of the latter include previous fertilization failure after cIVF, few or poor-quality oocytes, immature oocytes, advanced maternal age, preimplantation genetics test (PGT), cryopreserved oocytes, and unexplained infertility. The replacement of cIVF with ICSI in several non-male factor infertility cases is probably because some reproductive specialists consider that ICSI is associated with better reproductive outcomes. Unfortunately, data on reproductive outcomes in favor of ICSI over cIVF are limited or absent. Therefore, the factors that can help define the use of one technique over the other should be identified. These should include the likelihood of fertilization failure, potential risks of the procedure, and its costs. In this review, we aim to highlight the current guidelines, advantages, and limitations of the use of cIVF/ICSI for infertility treatment. Additionally, we provide a comprehensive review of the use of ICSI in indications other than severe male factor infertility.

How to select healthy sperm for intracytoplasmic sperm injection in samples with high sperm DNA fragmentation?

The body of evidence supports the negative impact of increased sperm DNA fragmentation (SDF) on natural fertility as well as assisted reproduction conditions. High SDF has been correlated with low pregnancy and delivery rates following intrauterine insemination. Also, high SDF is accused of reducing the rates of fertilization, implantation, pregnancy, and live birth following in-vitro fertilization (IVF). Despite no impact of high SDF on fertilization or pregnancy rates following intracytoplasmic sperm injection (ICSI), it has been correlated with poor embryo quality and a higher risk of miscarriage. Several methods have been introduced to help select sperm with the best DNA quality to be used in assisted reproductive technology procedures. These include magnetic-activated cell sorting, intracytoplasmic morphologically selected sperm injection, physiologic ICSI, and microfluidic sperm sorters, among others. This article aimed to discuss the impact of high SDF in infertile men on the reproductive outcome of couples undergoing IVF/ICSI. Additionally, this review highlights the principles, advantages, and limitations of different techniques that are currently used for the selection of sperm with intact DNA to be utilized for ICSI.

Sperm DNA fragmentation test: usefulness in assessing male fertility and assisted reproductive technology outcomes.

Male infertility is attributed to multiple factors including high levels of sperm DNA fragmentation (SDF). Conventional semen analysis continues to be the gold standard for diagnosis of male factor infertility around the world. However, the limitations of basic semen analysis have prompted the search for complementary assessments of sperm function and integrity. Sperm DNA fragmentation assays (direct or indirect) are emerging as important diagnostic tools in male infertility workups, and have been advocated for use in infertile couples for a variety of reasons. While a controlled degree of DNA nicking is required for appropriate DNA compaction, excessive fragmentation of sperm DNA is linked to impaired male fertility potential, decreased fertilization, poor embryo quality, recurrent pregnancy loss, and failure of assisted reproductive technology procedures. However, there is an ongoing debate regarding whether or not to employ SDF as a routine test for male infertility. This review compiles up-to-date information regarding the pathophysiology of SDF, the currently available SDF tests, and the role of SDF tests in natural and assisted conception conditions.

Time-lapse embryo monitoring: does it add to standard in-vitro fertilization/intra cytoplasmic sperm injection?

Since the first pioneering studies on time-lapse systems (TLSs) for embryo incubation, many things have changed. Two main factors influence the development of modern time-lapse incubators for human in-vitro fertilization (IVF): 1) the switch from traditional cell culture incubators to benchtops incubators, more suitable for human IVF; and 2) the improvement of imaging technology. Another major factor for the increase in the utilization of TLSs in IVF labs over the last decade was the advances in computer/wireless and smartphone/tablet technology, which allowed patients to see the footage of their growing embryos. Hence, more user-friendly features have allowed their introduction and routine use in IVF labs while image-capturing software has enabled storage and providing additional information to the patients concerning the development of their embryos. This review aims to describe the history and the different TLSs available in the market, to summarize the research and clinical results obtained by using this technology, and to reflect on how this technology is changing the modern IVF laboratory. The current limitations of TLSs will be also reviewed.

Are commercial warming kits interchangeable for vitrified human blastocysts? Further evidence for the adoption of a Universal Warming protocol.

PURPOSE: To study whether a new combination of different warming kits is clinically effective for vitrified human blastocysts. METHODS: This is a longitudinal cohort study analysing two hundred fifty-five blastocysts warming cycles performed between January and October 2018. Embryos were vitrified using only one brand of ready-to-use kits (Kitazato), whereas the warming procedure was performed with three of the most widely used vitrification/warming kits (Kitazato, Sage and Irvine) after patient stratification for oocyte source. The primary endpoint was survival rate, while the secondary endpoints were clinical pregnancy, live birth and miscarriage rates. RESULTS: We observed a comparable survival rate across all groups of 100% (47/47) in KK, 97.6% (49/50) in KS, 97.6% (41/42) in KI, 100% (38/38) in dKK, 100% (35/35) in dKS and 100% (43/43) in dKI. Clinical pregnancy rates were also comparable: 38.3% (18/47) in KK, 49% (24/49) in KS, 56.1% (23/ 41) in KI, 47.4% (18/38) in dKK, 31.4% (11/35) in dKS and 48.8% (21/ 43) in dKI. Finally, live birth rates were 29.8% (14/47) in KK, 36.7% (18/49) in KS, 46.3% (19/41) in KI, 36.8% (14/38) in dKK, 25.7% (9/35) in dKS and 41.9% (18/43) in dKI, showing no significant differences. CONCLUSION: This study confirmed the efficacy of applying a single warming protocol, despite what the "industry" has led us to believe, supporting the idea that it is time to proceed in the cryopreservation field and encouraging embryologists worldwide to come out and reveal that such a procedure is possible and safe.

A Simple and Efficient Solution to Eliminate Evaporation in Mammalian Embryo Cultures.

The aim of this brief report is to offer a solution for a problem that compromises the quality of in vitro-produced mammalian embryos. The harmful effects of evaporation-induced osmotic changes in mammalian embryo cultures have been recognized only recently. In this technical report, we describe a modified embryo culture dish (Humdish) that provides consistent >97% humidity and fully eliminates osmotic changes in the commonly used drop-under-oil culture systems from day 0 to 6. As an additional benefit, the Humdish also increases the temperature stability of cultures. If subsequent laboratory and clinical experiments prove its value, our suggested approach may help to improve the in vitro environment and quality of all preimplantation stage mammalian embryos, including the most sensitive ones produced from artificial gametes or by somatic cell nuclear transfer.

Back to the future: optimised microwell culture of individual human preimplantation stage embryos.

Although in vitro culture of human embryos is a crucial step in assisted reproduction, the lack of focused research hampers worldwide standardisation and consistent outcomes. Only 1.2% of research papers published in five leading journals in human reproduction in 2019 focused on in vitro culture conditions, creating the impression that the optimisation process has approached its limits. On the other hand, in vitro culture of mammalian embryos is based on old principles, while there is no consensus on basic issues as density, time, medium change, gas atmosphere and small technical details including the way of drop preparation. This opinion paper aims to highlight and analyse the slow advancement in this field and stimulate research for simple and affordable solutions to meet the current requirements. A possible way for advancement is discussed in detail. Selection of embryos with the highest developmental competence requires individual culture and modification of the widely used "drop under oil" approach. Current use of three-dimensional surfaces instead of large flat bottoms is restricted to time-lapse systems, but these wells are designed for optical clarity, not for the needs of embryos. The size and shape of the original microwells (Well of the Well; WOW) offer a practical and straightforward solution to combine the benefits of communal and individual incubation and improve the overall quality of cultured embryos.

"Universal Warming" protocol for vitrified oocytes to streamline cell exchange for transnational donation programs: a multi-center study.

PURPOSE: To investigate the clinical efficacy of a "Universal Warming" protocol, based on subsequent steps with 1 M and 0.5 M concentration of extracellular cryoprotectant (ECCP), on shipped oocytes. Oocytes are vitrified using different brands of ready-to-use kits which recommend that the use of their own warming kit and combining different vitrification/warming kits may have legal consequences for assisted reproductive (AR) centers, until this practice has been validated with clinical studies. METHODS: Retrospective multi-center transnational observational study. Number of oocytes warmed 1.898. Vitrification performed with vitrification kit (Kitazato, Japan); warming carried out randomly with two different kits: Kitazato warming kit and Vit Kit®-Thaw (FujiFilm Irvine, USA). Warmed oocytes were assigned to 2 groups: KK (Kitazato/Kitazato) 939, and KI (Kitazato/Irvine) 959. Primary endpoint: survival rate. Secondary endpoints: fertilization rate; blastulation rate; implantation rate; live birth rate. RESULTS: Survival was comparable between the groups: 84.6% (795/939) in group KK vs 82.1% (787/959) in group KI. Fertilization rate was lower (P = 0.027) in group KK (75.7%-602/795) than in group KI (80.4%-633/787). Blastulation and implantation and live birth rates were all statistically comparable between the study groups: blastulation rate was 58.5% (352/602) vs 57.8% (366/633); implantation rate was 41.5% (80/193) vs 45.9% (84/183); live birth rate was 52.5% (62/118) in KK and 45.0% (54/120) in KI. CONCLUSION: The use of this "Universal Warming" protocol simplifies vitrified oocyte exchange between AR centers in different countries, and overcomes potential regulatory/commercial/availability differences affecting clinical practice.