Should we perform oocyte accumulation to preserve fertility in women with Turner syndrome? A multicenter study and systematic review of the literature.

STUDY QUESTION: Should we perform oocyte accumulation to preserve fertility in women with Turner syndrome (TS)? SUMMARY ANSWER: The oocyte cryopreservation strategy is not well adapted for all TS women as their combination of high basal FSH with low basal AMH and low percentage of 46,XX cells in the karyotype significantly reduces the chances of freezing sufficient mature oocytes for fertility preservation. WHAT IS KNOWN ALREADY: An oocyte cryopreservation strategy requiring numerous stimulation cycles is needed to preserve fertility in TS women, to compensate for the low ovarian response, the possible oocyte genetic alterations, the reduced endometrial receptivity, and the increased rate of miscarriage, observed in this specific population. The validation of reliable predictive biomarkers of ovarian response to hormonal stimulation in TS patients is necessary to help practitioners and patients choose the best-personalized fertility preservation strategy. STUDY DESIGN, SIZE, DURATION: A retrospective bicentric study was performed from 1 January 2011 to 1 January 2023. Clinical and biological data from all TS women who have received from ovarian stimulation for fertility preservation were collected. A systematic review of the current literature on oocyte retrieval outcomes after ovarian stimulation in TS women was also performed (PROSPERO registration number: CRD42022362352). PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 14 TS women who had undergone ovarian stimulation for fertility preservation were included, representing the largest cohort of TS patients published to date (n = 14 patients, 24 cycles). The systematic review of the literature identified 34 additional TS patients with 47 oocyte retrieval outcomes after ovarian stimulation in 14 publications (n = 48 patients, n = 71 cycles in total). MAIN RESULTS AND THE ROLE OF CHANCE: The number of cryopreserved mature oocytes on the first cycle for TS patients was low (4.0 ± 3.7). Oocyte accumulation was systematically proposed to increase fertility potential and was accepted by 50% (7/14) of patients (2.4 ± 0.5 cycles), leading to an improved total number of 10.9 ± 7.2 cryopreserved mature oocytes per patient. In the group who refused the oocyte accumulation strategy, only one patient exceeded the threshold of 10 mature cryopreserved oocytes. In contrast, 57.1% (4/7) and 42.9% (3/7) of patients who have underwent the oocyte accumulation strategy reached the threshold of 10 and 15 mature cryopreserved oocytes, respectively (OR = 8 (0.6; 107.0), P = 0.12; OR= 11 (0.5; 282.1), P = 0.13). By analyzing all the data published to date and combining it with our data (n = 48 patients, n = 71 cycles), low basal FSH and high AMH concentrations as well as a higher percentage of 46,XX cells in the karyotype were significantly associated with a higher number of cryopreserved oocytes after the first cycle. Moreover, the combination of low basal FSH concentration (<5.9 IU/l), high AMH concentration (>1.13 ng/ml), and the presence of 46,XX cells (>1%) was significantly predictive of obtaining at least six cryopreserved oocytes in the first cycle, representing objective criteria for identifying patients with real chances of preserving an adequate fertility potential by oocyte cryopreservation. LIMITATIONS, REASONS FOR CAUTION: Our results should be analyzed with caution, as the optimal oocyte number needed for successful live birth in TS patients is still unknown due to the low number of reports their oocyte use in the literature to date. WIDER IMPLICATIONS OF THE FINDINGS: TS patients should benefit from relevant clinical evaluation, genetic counseling and psychological support to make an informed choice regarding their fertility preservation technique, as numerous stimulation cycles would be necessary to preserve a high number of oocytes. STUDY FUNDING/COMPETING INTEREST(S): This research received no external funding. The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

[What issues, changes and adaptations for French ART centers in the context of the new bioethics law?] / Quels enjeux et adaptations pour les centres d'AMP dans le cadre de la mise en place de la nouvelle loi de bioéthique ?

OBJECTIVE: This review intends to introduce the changes of the new Bioethics law in the reproductive field and its application in French ART centers. MATERIAL AND METHODS: The review details the main provisions of the Bioethics Law of August 2nd 2021 as well as the three decrees published since: the first one on September 29th 2021, which specifies in particular the age conditions to benefit from ART and self-preservation of one's gametes; another decree on December 31st, 2021, to set the terms and conditions for gamete self-preservation activities for non-medical reasons and the last decree on April 14th 2022, relating to the allocation of donated gametes and embryo donation. RESULTS: Since the law of August 2nd, 2021, access conditions to assisted reproductive technology (ART) have evolved in France. Previously based on pathological infertility or the risk of transmission of a serious disease, ART is now intended to respond to the parental project of a couple formed by a man and a woman, two women or an unmarried woman. With the widening of access conditions, the use of gamete donation will likely increase. The upcoming raise of children born from gamete donation has led the legislator to question their right to access their origin. From September 1st 2022, adults born from gamete donation will be able to request a special administrative authority in order to access the donor's non identifying data (age, physical characteristics, family and professional situation, motivation for the donation…) and/or the donor's identity. Moreover, the new bioethics law opens up the possibility of autologous gamete cryopreservation without medical reasons, under specific age conditions, in order to carry out an assisted reproduction technique later. If gametes are not used, autologous gamete preservation could also allow an increase in gamete donation. However, the modification of gamete donation conditions could suggest a short term decrease in donors' number. Finally, the new bioethics law further opens up research on human embryos and embryonic stem cells. CONCLUSION: The arrangements introduced by the Bioethics Law promulgated on August 2nd, 2021 represent a major revolution in the field of Reproductive Medicine and are expected to transform the practices of reproductive biology centers and CECOS in France.

[HLA-C KIR interactions and placental defects: Implications in ART pregnancy issues]. / Interactions HLA-C KIR et anomalies de la placentation : implications dans les issues de grossesses obtenues en AMP.

OBJECTIVE: The aim of this review is to update data concerning the impact of HLA-C KIR system on placental disorders and assess the involvement on ART clinical outcomes. METHOD: Ensuring the maintenance of human pregnancy requires the set up of immunological tolerance to prevent foetus rejection. This phenomenon involves different actors of the immune system: among them, uterine NK cells (uNK) hold specific KIR (killer-cell immunoglobulin-like) receptors linking to HLA molecules on the surface of trophoblastic cells at implantation. Many studies provided evidence that the specific interaction between maternal KIR and foetal HLA-C could influence the process of placentation; according to the KIR haplotype and the type of HLA-C, the interaction could be detrimental for placental function. We reviewed the latest data available regarding HLA-C KIR interactions and ART outcomes. RESULTS: The available results highlight a significant increase of preeclampsia risk and recurrent miscarriages when the maternal inhibitory haplotype KIR AA is present, this risk is all the more enhanced when the interaction occurs with foetal HLA-C2. Recent data suggest the consequences of this detrimental interaction in case of DET (double embryo transfer) or use of donor's oocytes in ART practice. On the other hand, maternal KIR AB or BB haplotypes haven't been related to an additional obstetrical risk, as well as the foetal HLA-C1 homozygous allotype. CONCLUSION: Despite the existence of many confoundings in current literature on the subject, interaction between maternal KIR and foetal HLA-C represent a promising target lead to broaden the spectrum of placental defects etiologies, especially in the reproductive health area.

[Environmental endocrine disruptors and fertility]. / Perturbateurs endocriniens environnementaux et fertilité.

Endocrine disruptor chemicals (EDCs) are ubiquitous contaminants in the environment, wildlife, and humans. During the last 20 years, several epidemiological, clinical and experimental studies have demonstrated the role of EDCs on the reduction of male and female fertility. The concept of foetal origins of adult disease is particularly topical in the field of reproduction. Moreover, exposure to EDCs during pregnancy has been shown to influence epigenetic programming of endocrine signalling and other important physiological pathways, and provided the basis for multi- and transgenerational transmission of adult diseases. However, the large panel of EDCs simultaneously present in the air, sol and water makes the quantification of human exposition still a challenge. Gas chromatography coupled with mass spectrometry, the measurement of total plasmatic hormonal bioactivity on stably transfected cell lines as well as the EDC analysis in hair samples are useful methods of evaluation. More recently, microRNAs analysis offers a new perspective in the comprehension of the mechanisms behind the modulation of cellular response to foetal or post-natal exposure to EDCs. They will help researchers and clinicians in identifying EDCs exposition markers and new therapeutic approaches in the future.

[Cesarean scare niche: Definition, diagnosis, risk factors, prevention, symptoms, adverse effects, and treatments]. / Isthmocèle : définition, diagnostic, facteurs de risque, prévention, symptômes, complications, et traitements.

OBJECTIVES: To review the definitions, diagnostic methods, risk factors, symptoms, and treatments for caesarean scar niche. METHODS: Review of the literature, critical reflection, and pragmatic advice. RESULTS: There is no consensus on the definition of caesarean scar niche. Some suggest an indentation≥2mm of the myometrium of the caesarean scar, but this is present in more than half of women with caesarean history and takes no account of woman's symptoms. The most popular diagnostic method is ultrasound±hysterosonography. Risks factors for niche are multiple Caesareans, Cesarean during labor with too low incision, and retroverted uterus. Symptoms include abnormal gynaecologic bleeding and pelvic pain, and their presence establish the "Caesarean scar syndrome". The risks of pregnancy with niche is poorly studied, but pregnancy is not contraindicated, even if the niche is untreated. The treatment of caesarean scar niche is mainly surgery and conservative. The former should be reserved for symptomatic patients, and those with secondary infertility and fertility treatment failure. Patients with residual myometrium thickness≥2.5mm may benefit from first-line hysteroscopic treatment, whereas a laparoscopic or vaginal approach could be offered in other cases. CONCLUSIONS: A pragmatic definition of caesarean scar niche as a disease including symptoms is the necessary prerequisite for the management of women. The treatment is mainly surgical, or conservative depending on the desire for subsequent pregnancy.

[Endometrial receptivity in assisted reproductive techniques: An aspect to investigate in embryo implantation failure]. / La réceptivité endométriale en aide médicale à la procréation : Une piste à ne pas oublier devant un échec d'implantation.

Infertility affects between 8 and 12% of reproductive-age couples worldwide. Despite improvements in assisted reproductive techniques (ART), live birth rates are still limited. In clinical practice, imaging and microscopy are currently widely used, but their diagnostic effectiveness remains limited. In research, the emergence of innovative techniques named OMICS would improve the identification of the implantation window, while progressing in the understanding of the pathophysiological mechanisms involved in embryo implantation failures. To date, transcriptomic analysis seems to be the most promising approach in clinical research. The objective of this review is to present the results obtained with the different approaches available in clinical practice and in research to assess endometrial receptivity in patients undergoing ART.

[Assessment of genital microbiota: An emerging approach in assisted reproductive techniques]. / Évaluation du microbiote génital : une approche émergente en assistance médicale à la procréation.

The genital microbiota actively participates in women's reproductive health. Indeed, a genital dysbiosis (microbial imbalance associated with adverse effects on host health) can lead to vaginal infections (such as mycoses or bacterial vaginosis). Recent data reported that genital dysbiosis (e.g. vaginal or endometrial) was associated with fewer chances of live births in assisted reproductive technologies (ART), via decreased pregnancy rates and an increased risk of miscarriages. The presence or diversity of certain bacterial strains (in particular Gardenellavaginalis, Proteobacteria, Lactobacillusjensenii, Lactobacilluscrispatus or Atopobiumvaginae) within the genital microbiota seem to be associated with the outcomes of ART cycles, suggesting new approaches to improve ART results. In this review, we aim at presenting the state of art on the association between the female genital microbiota and ART success. The diagnostic and therapeutic approaches (i.e. probiotics, antibiotic therapy and transplantation of vaginal microbiota) in the management of patients with altered microbiota will also be discussed. The confirmation of these data in the coming years could significantly improve the management of infertile patients in ART with a more personalized approach partially based on the female genital microbiotic profile.