In vitro culture of mechanically isolated murine primary follicles in the presence of human platelet lysate PLTMax.

OBJECTIVE: To develop a system for the culture of murine preantral ovarian follicles using Human Serum Albumin (HSA) and Human Platelet Lysate (PLTMax). METHODS: Mechanically isolated preantral follicles (N=146) were obtained from Swiss mice and cultured in DMEM:F12 medium for ten days in a 96-well plate with conical bottom. The medium was supplemented with penicillin, streptomycin, and equine chorionic gonadotropin. Additional proteins were tested in 4 test groups: G1: human serum albumin (HSA), G2: human platelet lysate (PLTM), and G3 and G4: HSA + PLTMax at lower and higher concentrations, respectively. Cellular vitality and oocyte morphology were evaluated on day 11 of culture. RESULTS: The highest follicular growth (3.4 fold) was achieved in HSA (G1), while a significantly lower (1.8 fold) growth was achieved in the presence of PLTM (G2, G4) and even further reduced (1.2 fold) when HSA and PLTM were combined (G3). Cellular vitality was close to 70-80% among the four groups, and the highest number of intact oocytes were found in G1. CONCLUSIONS: PLTM did not improve follicular development and oocyte maturation compared to HSA but preserved cell vitality.

Gonadotropin axis and semen quality in young Swiss men after cannabis consumption: Effect of chronicity and modulation by cannabidiol.

BACKGROUND: While cannabis is the most widely used recreational drug in the world, the effects of phytocannabinoids on semen parameters and reproductive hormones remain controversial. Cannabinoid receptors are activated by these compounds at each level of the hypothalamus-pituitary-gonadotropic axis. OBJECTIVES: To assess the impact of the consumption of Δ-9-tetrahydrocannabinol and cannabidiol on semen parameters, as well as on male reproductive hormone and endocannabinoid levels, in a cohort of young Swiss men. MATERIALS AND METHODS: The individuals in a Swiss cohort were divided according to their cannabis consumption. In the cannabis user group, we determined the delay between the last intake of cannabis and sample collection, the chronicity of use and the presence of cannabidiol in the consumed product. Urinary Δ-9-tetrahydrocannabinol metabolites were quantified via gas chromatography-mass spectrometry. Blood phytocannabinoids, endocannabinoids and male steroids were determined via liquid chromatography-mass spectrometry/mass spectrometry, and other hypothalamus-pituitary-gonadotropic axis hormones were determined via immunoassays. Semen parameters such as sperm concentration and motility were recorded using computer-assisted sperm analysis. RESULTS: Anandamide, N-palmitoyl ethanolamide, androgens, estradiol and sex hormone binding globulin levels were all higher in cannabis users, particularly in chronic, recent and cannabidiol-positive consumers. Gonadotropin levels were not significantly different in these user subpopulations, whereas prolactin and albumin concentrations were lower. In addition, cannabis users had a more basic semen pH and a higher percentage of spermatozoa with progressive motility. However, the two latter observations seem to be related to a shorter period of sexual abstinence in this group rather than to the use of cannabis. CONCLUSIONS: Because both cannabidiol and Δ-9-tetrahydrocannabinol are frequently used by men of reproductive age, it is highly relevant to elucidate the potential effects they may have on human reproductive health. This study demonstrates that the mode of cannabis consumption must be considered when evaluating the effect of cannabis on semen quality.

Association between self-reported mobile phone use and the semen quality of young men.

OBJECTIVES: To investigate the association between mobile phone exposure and semen parameters. DESIGN: A nationwide cross-sectional study. SETTING: Andrology laboratories in close proximity to 6 army recruitment centers. PATIENTS: In total, 2886 men from the general Swiss population, 18-22 years old, were recruited between 2005 and 2018 during military conscription. INTERVENTION: Participants delivered a semen sample and completed a questionnaire on health and lifestyle, including the number of hours they spent using their mobile phones and where they placed them when not in use. MAIN OUTCOME MEASURES: Using logistic and multiple linear regression models, adjusted odds ratios and ß coefficients were determined, respectively. The association between mobile phone exposure and semen parameters such as volume, sperm concentration, total sperm count (TSC), motility, and morphology was then evaluated. RESULTS: A total of 2759 men answered the question concerning their mobile phone use, and 2764 gave details on the position of their mobile phone when not in use. In the adjusted linear model, a higher frequency of mobile phone use (>20 times per day) was associated with a lower sperm concentration (adjusted ß: -0.152; 95% confidence interval: -0.316; 0.011) and a lower TSC (adjusted ß: -0.271; 95% confidence interval: -0.515; -0.027). In the adjusted logistic regression model, this translates to a 30% and 21% increased risk for sperm concentration and TSC to be below the World Health Organization reference values for fertile men, respectively. This inverse association was found to be more pronounced in the first study period (2005-2007) and gradually decreased with time (2008-2011 and 2012-2018). No consistent associations were observed between mobile phone use and sperm motility or sperm morphology. Keeping a mobile phone in the pants pocket was not found to be associated with lower semen parameters. CONCLUSION: This large population-based study suggests that higher mobile phone use is associated with lower sperm concentration and TSC. The observed time trend of decreasing association is in line with the transition to new technologies and the corresponding decrease in mobile phone output power. Prospective studies with improved exposure assessment are needed to confirm whether the observed associations are causal.

Association between terbinafine hydrochloride and sperm DNA fragmentation - case report.

OBJECTIVE: To present the case of a man with normozoospermia and a high level of fragmented spermatozoa, which origin seems to be associated with long-term treatment with terbinafine hydrochloride. CASE DESCRIPTION: A 20-year-old male healthy patient, with no history of disease and addictions, used an antifungal (terbinafine hydrochloride) for one year to treat a toenail. During this treatment, he participated in a study to evaluate a method of sperm DNA fragmentation analysis. He had 99% fragmented sperm, primarily attributed to prolonged abstinence. The samples that were analyzed later indicated that the high fragmentation could be associated with the antifungal treatment and that with a 2-day abstinence and absence of treatment the fragmentation rate was again comparable with that of fertile men (15%). CONCLUSION: Terbinafine hydrochloride is likely to cause problems in male fertility, mainly affecting DNA sperm integrity. Further studies are needed to confirm this observation and to determine at what level of the genitourinary tract the alteration of DNA occurs.

In vitro maturation of Mus musculus mice oocytes after hyperosmotic shock induced by vitrification solutions.

OBJECTIVE: To evaluate in vitro oocyte maturation rates in embryonic culture medium after induction by hyperosmotic shock caused by exposure to vitrification solutions. METHODS: Bilateral oophorectomy was performed on 20 prepubescent female mice (Swiss). Immature (Prophase I) oocytes (N = 400) were obtained by ovarian dissection, divided into 4 groups, and transferred to culture dishes containing fertilization medium (Sydney IVF Fertilization Medium, Cook® Medical). The control group (CG) did not receive treatment, the test groups (G1, G2, G3) were treated with vitrification solution - 2 (VI-2: 14 M sucrose + ethylene glycol and dimethyl sulfoxide) for 30 seconds and subsequently: G1: 30 seconds in devitrification solution - 2 (DV-2: 0.5M sucrose); G2: 60 seconds DV-2; G3: 60 seconds DV-1(1M sucrose) and 180 seconds DV-2. All groups were cultivated for 24 hours in an incubator at 37ºC and 5% CO2 (Thermo model 3110). After this period, we checked their maturation status. RESULTS: Oocytes exposed to VI-2, DV-1 and DV-2 (G3) showed the highest rate of competence in resuming meiosis and reaching the MII stage; however, there was no statistically significant difference (G3 = 50.5% - 49/97; CG = 27.8% - 10/30). CONCLUSIONS: Oocyte exposure to vitrification solutions, in order to cause osmotic shock, did not interfere with the resumption of meiosis in mice oocytes.

Semen endocannabinoids are correlated to sperm quality in a cohort of 200 young Swiss men.

BACKGROUND: A role for endocannabinoids in the male and female reproductive systems has been highlighted during the recent decades. Some of these compounds bind the cannabinoid CB1 receptor, which is abundantly expressed in the central nervous system but also present in the reproductive system, while others act as 'entourage compounds' modulators. OBJECTIVES: The present study aimed at evaluating the relationship between sperm quality and endocannabinoid profiles in a cohort of 200 young Swiss men and whether the presence of specific xenobiotics could influence these profiles. MATERIALS AND METHODS: Semen analysis was performed according to WHO guidelines. Endocannabinoid profiles in blood and semen, as well as bisphenol A and S in urine, were determined by LC-MSMS methods. The presence of selected drugs was tested in urine by immunological screening, and urinary tetrahydrocannabinol (THC) metabolites were quantified by GC-MS. RESULTS: Anandamide concentrations in seminal fluid and oleoylethanolamide (OEA) concentrations in blood serum appeared inversely correlated with sperm motility, while semen palmytoylethanolamide (PEA) was positively linked to sperm concentration. Moreover, OEA and PEA in seminal fluid were associated with better sperm morphology. Interestingly, the concentrations of the same endocannabinoids measured in both blood and semen were not correlated, and the presence of THC metabolites in some individuals was linked to lower concentrations of endocannabinoids. CONCLUSIONS: In the context of the general decline of the sperm count observed within the male population, endocannabinoids in semen constitute a class of promising biochemical markers that open new perspectives as a complement for the usual evaluation of semen quality or for the toxicological screening of individuals' exposure to putative endocrine disruptors.

Wistar rats immature testicular tissue vitrification and heterotopic grafting.

OBJECTIVE: To evaluate the efficiency of two vitrification protocols for rat immature testicular tissue and heterotopic transplantation. METHODS: Twenty-four pre-pubertal Wistar rats were divided into three groups (n=8). After orchiectomy, testicular fragments (3mm) from Groups 1 and 2 were vitrified with different cryoprotectant concentration solutions, using sterile inoculation loops as support. After warming up, the fragments were submitted to cell viability assessment by Trypan blue and histological evaluation. Vitrified (Groups 1 and 2) and fresh (Group 3) fragments were grafted to the animals periauricular region. After 8 weeks of grafting, the implant site was histologically analyzed. RESULTS: The viability recovery rate from Group 1 (72.09%) was higher (p=0.02) than that from Group 2 (59.19%). Histological analysis showed similar tubular integrity between fresh fragments from Groups 1 and 3. Group 2 samples presented lower tubular integrity. We ran histological analyses in the grafts from the Groups. In all groups, it was possible to see the implant site, however, no fragment of testicular tissue or signs of inflammation were histologically found in most samples from Groups 1 and 3. In one sample from Group 2, we found degenerated seminiferous tubules with necrosis and signs of an inflammatory process. In another sample from Group 2, we found seminiferous tubules in the implant site. CONCLUSION: The vitrification of pre-pubertal testicular tissue of rats showed little damage to cell viability through histological analysis when we used cryoprotectants in a lower concentration. Heterotopic transplantation could not preserve the structural organization of the testicular tissue.

Steroid profiles in both blood serum and seminal plasma are not correlated and do not reflect sperm quality: Study on the male reproductive health of fifty young Swiss men.

Steroids play an important role in sperm production and quality. These hormones have been extensively studied in blood, but poorly investigated in semen. The purpose of our study was to evaluate the relationship between sperm quality and steroid profiles in blood and semen in a small cohort of young Swiss men. Another objective was to determine whether the presence of xenobiotics or drugs could influence these profiles. Semen analysis was performed according to WHO guidelines, and steroid profiles in blood serum and seminal plasma were determined by two complementary approaches: a targeted investigation involving the quantification of a limited number of relevant steroids for testing putative correlations with sperm parameters and a global "steroidomic" analysis highlighting their complex metabolic relationship. Results showed that steroid profiles are distinct within blood and seminal fluid. No significant correlation was found between individual steroids measured in blood and in semen, demonstrating the relevance of assessing hormone levels in both fluids. Moreover, testosterone and androstenedione levels were significantly correlated in semen but not in blood. None of the evaluated spermiogram parameters was linked to steroid levels measured in any medium. The steroidomic analyses confirmed that the steroids present in both fluids are different and that there is no correlation with spermiogram parameters. Finally, upon toxicological screening, we observed that all the three samples positive for tetrahydrocannabinol, which is known to act as an endocrine disruptor, displayed low seminal testosterone concentrations. In conclusion, we did not find any evidence suggesting using steroid profiles, neither in blood nor in semen, as surrogates for sperm analyses. However, steroid profiles could be useful biomarkers of individual exposure to endocrine disruptors.

Ovarian tissue vitrification and heterotopic autologous transplantation in prepubertal Wistar rats.

OBJECTIVE: To evaluate the efficiency of ovarian tissue heterotopic autografting after vitrification in prepubertal rats. METHODS: Fragments of excised ovaries from prepubertal rats were used after assessing post-warming cellular viability, to determine the best vitrification protocol prior to retroauricular autografting. Pre-pubertal females (N=24) were castrated and divided into three group: Group 1 - fresh ovarian tissue transplantation; Group 2 - vitrified/warmed tissue transplantation; Group 3 - bilateral oophorectomy without transplantation. The ovarian fragments were exposed to solutions from the Ingamed® commercial kit, allocated in bacteriological loops and immersed in liquid nitrogen. Sixty days after transplantation, a vaginal mucus sample was collected for cytology tests, followed by sacrificing the animal, performing a cardiac puncture for collecting a blood sample to determine luteinizing hormone and estradiol levels, and excision of the transplanted fragment for histology tests. RESULTS: Vaginal cytology revealed that 87.5% of females from groups 1 and 2 had estrus while all females in Group 3 remained in diestrus. The mean LH value in groups 1 (0.08 mIU/mL) and 2 (0.34 mIU/mL) were statistically different from that of Group 3 (2.27 mIU/mL). E2 values did not differ between the groups. The histological analysis of Group 1 excised grafts versus those from Group 2 showed a higher percentage of primary follicles (62.5% vs. 12.5%), developing follicles (75% vs. 25%), corpus luteum (37.5% vs. 12.5%) and stromal region (100% vs. 87.5%). CONCLUSION: This study indicated that pre-pubertal ovarian tissue vitrification can be used to preserve fertility and to restore endocrine function in castrated rats.

Effects of energy drinks on biochemical and sperm parameters in Wistar rats

BACKGROUND: The present study evaluates the effects of energy drinks on the reproductive and biochemical parameters of adult male rats. METHODS: A total of 40 male rats (Wistar) were exposed to an energy drink mixed with the drinking water for a period of 120 days. The animals were divided into four groups and exposed to increasing therapeutic doses (DT) of an energy drink, based on allometric extrapolation, resulting in values (mL/day) per animal of 250 g: DT1 2.36 mL, DT3 7.47 mL, and DT6 14.16 mL. The control group (CTRL) consumed water only. During the treatment, the rats were assessed for signs of toxicity. After treatment, the animals were sacrificed and their organs were weighed. Sperm parameters (motility, concentration, and morphology) were evaluated. The biochemical markers alanine eamino transferase, aspartate amino transferase, alkaline phosphatase, lactic dehydrogenase, urea, creatinine, creatine phosphokinase, and creatine kinase MB fraction were measured, in addition to total cholesterol and testosterone. RESULTS: There was a significant decrease (p< 0.05) in the concentration of sperm in the treated groups (DT18.5 ± 0.7; DT3 7.2 ± 0.9; DT6 8.4 ± 0.9) compared to the control group (12.3 ± 1.2). No difference was observed with respect to relative weights of the animals'organs, water consumption, signs of toxicity, behavioral changes, biochemical markers, and sperm motility and morphology. CONCLUSION: The long-term consumption of energy drinks interferes negatively with sperm concentration, without affecting sperm motility and morphology or altering the hepatic, cardiac, or renal functions

The effects of storing and transporting cryopreserved semen samples on dry ice.

OBJECTIVE: This study aimed to test the effects on sperm viability of transporting cryopreserved semen samples on dry ice. METHODS: Twenty normozoospermic semen samples were cryopreserved and divided into five groups. The samples in Group 1 were immersed in liquid nitrogen throughout the experiment in cryogenic storage tanks; the cryopreserved straws in Group 2 were placed in a Styrofoam box containing dry ice and kept under these conditions for 48 hours; the samples in Group 3 were kept for 48 hours on dry ice under the same conditions as the Group 2 samples, and were then moved to a storage tank filled with liquid nitrogen; Group 4 samples were also kept for 48 hours in dry ice storage, and the Styrofoam box containing the samples was shipped by plane to assess the effects of shipping; the samples in Group 5 were shipped together with the Group 4 samples and were placed in a storage tank with liquid nitrogen after spending 48 hours stored on dry ice. After thawing, sperm parameters were analyzed for viability, vitality, and motility; spermatozoa were also tested for mitochondrial activity. RESULTS: Significant decreases in motility recovery rates (P=0.01) and vitality (P=0.001) were observed in all groups when compared to the control group. Mitochondrial activity was significantly decreased only in Group 5 (P=0.04), as evidenced by greater numbers of sperm cells not stained by reagent 3,3'-diaminobenzidine. CONCLUSIONS: Transportation did not affect the quality of cryopreserved semen samples, but dry ice as a means to preserve the samples during transportation had detrimental effects upon the sperm parameters assessed in this study.

Sperm Selection Using Three Semen Processing Techniques.

OBJECTIVE: This study aimed to assess the efficiency, in terms of recovered motile spermatozoa with normal morphology, of three sperm selection techniques: migration- sedimentation (SS), swim-up from fresh semen (SF), and swim-up from washed (SL) sperm. METHODS: Samples from 20 normozoospermic men were divided into three equal aliquots and processed in parallel. SS was performed in a Jondet tube, using 1 ml of semen and 2.5 ml of Human Tubal Fluid medium (HTF+10% Synthetic Serum Supplement, Irvine, USA). For SF, 1 ml of HTF was layered over 1 ml of fresh semen (SF). For SL, 1 ml of sperm was first centrifuged (300 g, 10 min) and the pellet resuspended in 1 ml of HTF; a second layer of HTF was placed on top. Migration time was 1h (SF and SL) and 1h30' for SS at 37°C. After migration, 200 µl were removed from the top layer (SF, SL) and from the central cone (SS). Concentration, morphology and motility were determined. RESULTS: Recovery rates were 25% for SS, 10.1% for SF and 4.5% for SL. SS recovery rate was significantly higher (P<0.01) than the two swim-up techniques. Total motility was statistically different (P<0.001), with 93.6% for SS, 91.2% for SF, and 77% for SL. Sperm morphology was similar between the three techniques (P= 0.12). CONCLUSION: SS is an efficient technique for the recovery of motile spermatozoa from native semen preparations and yielded better results than SF and SL. Routine use for assisted reproduction remains to be evaluated.

Effect of embryo culture media on birthweight and length in singleton term infants after IVF-ICSI.

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.

Sperm toxicity of "nonspermicidal" lubricant and ultrasound gels used in reproductive medicine.

Three commercial, nonspermicidal gels used in fertility practice were found to be toxic to sperm in a 24-hr sperm survival assay; these included Felis, Replens, and Aquasonic Gel, which is used for transvaginal ultrasound during ovulation monitoring. In contrast, Pre-Seed did not cause any sperm toxicity, suggesting its appropriate use by patients who are trying to conceive, as well as clinicians during fertility procedures.

Effects of TNF antagonists on sperm characteristics in patients with spondyloarthritis.

OBJECTIVE: To study the influence of tumour necrosis factor (TNF) antagonists on spermatogenesis in a cohort of patients with spondyloarthritis (SpA). PATIENTS AND METHODS: Semen samples of 26 patients with SpA were analysed according to WHO 1999 guidelines with and without TNF blocking agents (infliximab, etanercept or adalimumab). RESULTS: were compared with semen samples of 102 healthy volunteers. Results Sperm abnormalities were found in 10/11 patients without anti-TNF therapy. The sperm of these 11 patients had significantly poorer motility (p=0.001) and vitality (p=0.001) than found in 15 patients tested during longstanding anti-TNF therapy, but sperm concentration and morphology were similar in the two groups. There was no significant difference of sperm quality between healthy controls and anti-TNF treated patients with SpA. Notably, sperm abnormalities were also found in 102 healthy controls. CONCLUSION: Sperm abnormalities are a common finding in healthy men, they are more pronounced in patients with active SpA. The sperm quality of patients with SpA with inactive disease receiving long-term TNF inhibition is comparable to that in healthy controls. The data support continuation of anti-TNF treatment when fatherhood is planned.

Core data for assisted reproductive technology registers: results of a consensus meeting.

In Europe, assisted reproductive technology (ART) is monitored in national registers but the definitions used and the recorded data vary from one register to another. In order to provide the stakeholders in this field with the most useful information and avoid an intolerable administrative burden for individual clinics, it is important to agree what constitutes core data for national registers. To do this, experts from 24 European countries met in March 2007 in Lausanne under the auspices of the Fondation pour l'Andrologie, la Biologie et l'Endocrinologie de la Reproduction (FABER) to discuss what constitutes core data for national assisted reproductive technology (ART) registers. Delegates concluded that only mainstream, non-experimental techniques should be included. Surrogate endpoints should be avoided. Data should be clearly defined and quantifiable, relevant to a majority of stakeholders and include factors of major ethical concerns and safety data. Data should not be recorded if they could be more appropriately collected through linkage with other national registers.

Morphological scoring of human pronuclear zygotes for prediction of pregnancy outcome.

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.

What is the most relevant standard of success in assisted reproduction?: The cumulated singleton/twin delivery rates per oocyte pick-up: the CUSIDERA and CUTWIDERA.

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.

Number of transferred embryos: how to reduce multiple pregnancies.

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.

Hatching: how to select the clinical indications.

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.