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Testicular tissue cryopreservation is the only option of fertility preservation in prepubertal boys. While it is considered experimental, since procedures to obtain mature spermatozoa from prepubertal testicular tissue are still under development, testicular tissue cryopreservation programs have emerged worldwide. Our aim was to study the feasibility and safety of a program of testicular tissue cryopreservation in prepubertal and adolescent boys facing gonadotoxic treatment in three University hospitals in Switzerland. Testicular tissue cryopreservation was accepted by 90% of families, with a total of 35 patients included. The average patient age was 8.5 years (range 7 months to 18.5 years). Malignancies were the most common diagnosis (31 patients, 88.6%) with 16 (45.7%) solid tumors and 15 (42.9%) hematological malignancies. Four (11.4%) patients had a benign condition. The main indication for testicular tissue cryopreservation was conditioning for hematologic stem cell transplantation (25 patients, 71.4%). Testicular tissue was cryopreserved according to the freezing protocol of Louvain Catholic University (Belgium), which includes either only immature testicular tissue freezing, or mature and immature testicular tissue freezing depending on the age of the patient and the presence or absence of haploid cells. The median number of spermatogonia per tubule cross-section was 2 (range 0-6) and spermatozoa were found in only one patient. Tumoral cells were found in one testicular biopsy of a leukemic patient. There were two minor adverse events and none of them required medical treatment or surgical revision. Five patients died during follow-up. Our data demonstrate the feasibility and safety of a program of testicular tissue cryopreservation coordinated by a multidisciplinary team of fertility preservation. Despite the experimental aspect of the procedure, the acceptation rate was high, which highlights the willingness of families and patients to participate in testicular tissue cryopreservation.

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Aim: Sperm cryopreservation (SCP) should be offered to every adolescent before gonadotoxic treatment, but experience in this age range is still relatively limited. The goal of this study is to assess how to optimize this procedure. Methods and Patients: One hundred thirty-three patients between 12 and 20 years old, who underwent SCP between 1980 and 2017, were included. Baseline data (age, indication for SCP, and semen parameters at freezing) and follow-up data (outcome of sperm straws and follow-up of sperm quality) were collected and analyzed. Results: SCP is feasible from the age of 12. Semen assessment parameters at this age were close to parameters of adults. However, we observed quantitative impairments in testicular tumors and qualitative impairments in leukemia and bone marrow failure. Four patients (3%) used their cryopreserved semen for medically assisted reproduction, 15 patients died (11.3%), 18 asked for destruction of their straws (13.5%), and nine samples were destroyed because of lack of news (6.8%). Very few patients underwent a sperm analysis after treatment. Conclusions: SCP is an efficient, still underused, procedure for adolescents and young adults. Cryopreserved sperm is rarely used and rarely destroyed, but studies with a longer follow-up are needed to better assess these observations. Follow-up with a specialist of reproductive medicine is valuable for better information of the patient.

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In Switzerland, since modifications of the law regulating reproductive medicine introduced the 1rst of September 2017, preimplantation genetic testing (PGT) has been legalised. Infertile couples undergoing in vitro fertilization (IVF) can benefit from this technology by detecting which embryos are aneuploid (ie abnormal number of chromosomes, PGT-A). This is performed in order to transfer euploid embryos (normal number of chromosomes) and to optimise success, though data are limited. Couples at risk of transmitting a severe monogenic disease or unbalanced translocation can undergo PGT for monogenic disease or chromosomal structural rearrangements (PGT-M/SR). These tests are subject to strict legal criteria. Their clinical application needs to be approved through a multidisciplinary approach taking into account legal and ethical issues while respecting the autonomy of the couples.

Depuis le 1er septembre 2017, les tests génétiques préimplantatoires (PGT) sont autorisés en Suisse suite aux modifications de la loi sur la procréation médicalement assistée (LPMA). Les couples infertiles qui effectuent une fécondation in vitro (FIV) peuvent bénéficier d'un PGT des aneuploïdies (PGT-A) dans le but de transférer des embryons euploïdes (nombre normal de chromosomes) et ainsi optimiser leurs chances de succès, sous réserve de données encore limitées. Les couples à risque de transmettre une maladie monogénique grave ou une translocation déséquilibrée peuvent avoir recours au PGT d'une anomalie d'un gène unique ou d'une anomalie de structure de chromosome (PGT-M/SR), dans les limites d'un cadre légal strict. Leur mise en pratique doit être décidée de manière pluridisciplinaire en tenant compte des enjeux légaux et éthiques dans le respect de l'autonomie des couples.

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Acute leukaemia is a life-threatening disease that needs treatment without delay. Fertility preservation is recommended, but often not possible because of the necessity to start treatment as soon as possible. The present study is a retrospective single-centre analysis of 459 patients diagnosed with acute leukaemia between 2002 and 2012. Sperm or oocyte preservation was successfully performed in only 29 (6%) patients. Of the 150 children, no paediatric patient sample was taken. The collected samples enabled the conception of 2 children by in vitro fertilisation; in addition, 3 spontaneous, non-assisted births in partners of male patients were observed. Fertility preservation is important but difficult to accomplish in patients with acute leukaemia; more efforts are clearly needed to preserve fertility in long-term survivors of acute leukaemia.

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The development of assisted reproductive technology (ART) has led to the birth of nearly 6 million children since the first IVF baby in 1978. For many years, it was routine practice to transfer multiple embryos in order to obtain the highest pregnancy rates. This strategy has induced a dramatic increase in multiple pregnancies and the associated complications for the mother and the child. Following better awareness of these issues, ART specialists have tried to reduce multiple pregnancy rates with the goal of producing a single, healthy full term baby. Improvement in embryo culture and cryopreservation are the key factors leading to the strategy of elective single embryo transfer (eSET) which represents the best option to achieving this goal. However eSET strategy needs to be implemented in good prognosis patient with good quality embryos.

Le développement des techniques de procréation médicalement assistée (PMA) a permis la naissance de presque 6 millions d'enfants depuis le premier bébé né par FIV en 1978. Pendant de nombreuses années, le transfert de plusieurs embryons était réalisé de routine afin d'obtenir les meilleurs taux de grossesses. Cette pratique a abouti à une augmentation inquiétante des grossesses multiples et des complications associées pour la mère et l'enfant. Les acteurs de la PMA ont alors eu comme but la naissance à terme d'un enfant en bonne santé. Les techniques de culture et de cryoconservation d'embryons ont permis de développer des stratégies de transfert électif d'un seul embryon (eSET). Toutefois, pour ne pas diminuer les chances de grossesses, l'eSET doit être utilisé chez des patientes à bon pronostic et avec des embryons de bonne qualité.

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QUESTIONS UNDER STUDY: To investigate if two distinct, commercially available embryo culture media have a different effect on birthweight and length of singleton term infants conceived after IVF-ICSI. METHODS: University hospital based cohort study. Between 1 January 2000 and 31 December 2004, patients conceiving through IVF-ICSI at the University Hospital, Lausanne have been allocated to two distinct embryo culture media. Only term singleton pregnancies were analysed (n = 525). Data analysis was performed according to two commercially available culture media: Vitrolife (n = 352) versus Cook (n = 173). Analysis was performed through linear regression adjusted for confounders. Media were considered equivalent if the 95% confidence interval lay between -150 g/+150 g. RESULTS: Length, gestational age and distribution of birthweight percentiles did not differ between groups (for both genders). Analysis of the whole cohort, adjusted for a subset of confounders, resulted in a statistically not different mean birthweight between the two groups (Vitrolife +37 g vs Cook, 95%CI: -46 g to 119 g) suggesting equivalence. Adjustment for an enlarged number of confounders in a subsample of patients (n = 258) also revealed no relevant mean birthweight difference of +71 g (95%CI: -45 g to 187 g) in favour of Vitrolife; however, lacking power to prove equivalence. CONCLUSIONS: Our data suggest that significant differences in birthweight due to these two distinct, commercially available embryo culture media are unlikely.

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Due to constant progress in oncology, survival rates of patients (children and adults) with cancer are increasing. Consequently, the reproductive future of young cancer patients needs to be addressed carefully. Fertility preservation techniques are available and issues such as the time available for fertility treatments, patients' age, presence of a partner and patients' personal wishes have to be considered. In Switzerland, a first therapeutic network (Réseau Romand de Cancer et Fertilité), was created in the French speaking part of Switzerland in 2006. Since 2010, a global Swiss network (FertiSave) has been created. The goal of these networks is to maximise the safety and efficacy of fertility preservation options offered to cancer patients without compromising their oncological prognosis. Patients' needs have to be identified, the therapeutic options evaluated rapidly and the optimal treatment promptly implemented in these urgent situations. This article reviews the fertility preservation options currently available and makes recommendations for different specific cancer situations, consistent with the latest scientific evidence and in general agreement with international recommendations.

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Improvement in cancer treatments resulted in an increased number of men surviving cancer. Quality of life has become an important issue in these patients. Anti cancer treatments might have transient or definitive harmful effects on male fertility. Sperm cryoconservation is currently the only proven method to preserve fertility in patients undergoing oncologic treatment. It should be proposed to every patient at reproductive age before chemotherapy, radiotherapy or any surgery involving reproductive tract. Despite low use rate, this simple method could allow patients presenting infertility after treatment to father a child.

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BACKGROUND: As embryo selection is not allowed by law in Switzerland, we need a single early scoring system to identify zygotes with high implantation potential and to select zygotes for fresh transfer or cryopreservation. The underlying aim is to maximize the cumulated pregnancy rate while limiting the number of multiple pregnancies. METHODS: In all, 613 fresh and 617 frozen-thawed zygotes were scored for proximity, orientation and centring of the pronuclei, cytoplasmic halo, and number and polarization of the nucleolar precursor bodies. From these individual scores, a cumulated pronuclear score (CPNS) was calculated. Correlation between CPNS and implantation was examined and compared between fresh and frozen-thawed zygotes. The effect of freezing on CPNS was also investigated. RESULTS: CPNS was positively associated with embryo implantation in both fresh and frozen zygotes. With similar CPNS, frozen zygotes presented implantation rates as high as those of fresh zygotes. Nucleolar precursor bodies pattern and cytoplasmic halo appeared as the most important factors predictive of implantation for both types of zygotes, while pronuclei position was specifically relevant for frozen-thawed zygotes. Freezing induced an alteration of most zygote parameters, resulting in a significantly lower CPNS and a lower pregnancy rate. CONCLUSIONS: CPNS may be used as a single prognostic tool for implantation of both fresh and frozen-thawed zygotes. Lower CPNS values of frozen-thawed zygotes may also be indicative of freezing damage to zygotes. Successful implantation of frozen zygotes despite lower CPNS suggests that they may recover after thawing and in vitro culture.

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National and international registries are essential tools for establishing new standards and comparing success rates, but they do not take into account the total pregnancy/delivery rate per oocyte recovery. In Switzerland and Germany, because of legal constraints, a maximum of three two-pronuclear zygotes are allocated for transfer whereas all the supernumerary pronuclear zygotes are immediately cryopreserved, preventing selection of the transferred embryos. We report on a 10 years' experience (1993-2002) of our centre which performs transfers of unselected embryos and cryopreservation at the two-pronuclear zygote stage. As approximately 30% of all deliveries are from cryo cycles, it is essential to take into account the contribution of the cryo transfers, and we propose therefore to evaluate, as a measure of IVF performance, the cumulated delivery rate per oocyte pick-up. This delivery rate is broken down further into the cumulated singleton delivery rate (CUSIDERA) and the cumulated twin delivery rate (CUTWIDERA). The sum (S) of these two rates is a measure of efficacy while the ratio CUTWIDERA/S as a percentage is a measure of safety of IVF treatments. Using these new indexes, the average 10 year efficacy and safety of our IVF programme were 26 and 19%, respectively. Both CUSIDERA and CUTWIDERA can be calculated easily in any clinical situation and yield useful parameters for patient counselling and internal/external benchmarking purposes.

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Because the diagnostic tools for predicting whether an early cleavage stage embryo can lead to a viable pregnancy are still elusive, transfer of more than one embryo remains quite common. However, the only way to reduce multiple pregnancies, considered as the main adverse effect of assisted reproductive technology, is to transfer a single embryo. In countries such as Switzerland and Germany, the law allows cryopreservation only at the 2-pronuclear stage. This restricts considerably the possibility of selecting the embryos to be transferred. Therefore, a good cryopreservation program at the 2-pronuclear stage is an essential tool to optimize the efficiency of in vitro fertilization (IVF). We therefore recommend the Cumulated Singleton Delivery Rate (CUSIDERA) as a measure of standard IVF efficiency. This rate averages approximately 23.5% when calculated over the last 10 years in our unit and reaches a value above 35% for patients with more than 10 zygotes. Elective single-embryo transfers and the decrease of iatrogenic multiple pregnancies in IVF remain dependent on better prognostic tools for the appropriate selection of patients, gametes, and zygotes.

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Currently, most fertility centers around the world use assisted hatching (AH) techniques to help embryo release out of the zona pellucida (ZP) and thus increase the implantation rate. For the last 13 years, several retrospective and prospective studies, assessing AH in different clinical indications, have given disparate results, making the selection of patients or embryos in need of this treatment complex. The most relevant conclusion obtained so far is that AH has a beneficial effect in women with repeated failures of embryo implantation. The place of AH in clinical practice in comparison with other approaches has to be reevaluated based on the selection of viable embryos using strict morphometric criteria and/or prolonged culture up to the blastocyst stage. Finally, the potential value of AH for indications other than repeated failure has to be weighed carefully to make sure that AH does not reduce the chances of implantation.

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