Lisa Dovere

Bio: Lisa Dovere is an academic researcher. The author has contributed to research in topics: Embryo transfer & Blastocyst. The author has an hindex of 6, co-authored 12 publications receiving 186 citations.

Associations of blastocyst features, trophectoderm biopsy and other laboratory practice with post-warming behavior and implantation.

Abstract: Study question Are trophectoderm biopsy or other pre-vitrification features or laboratory practices associated with differences in blastocyst post-warming behavior (degeneration, re-expansion and live birth after single embryo transfer (SET))? Summary answer Blastocyst morphology, day of full development and artificial shrinkage (either laser-assisted or biopsy-induced) are the pre-vitrification parameters/practices most strongly associated with post-warming behavior and implantation potential while there was no association with trophectoderm biopsy. What is known already Since the introduction of vitrification, the adoption of cycle segmentation, freeze-all and SET policies, as well of trophectoderm biopsy-based aneuploidy testing (i.e. pre-implantation genetic testing for aneuploidies (PGT-A)), the number of blastocysts vitrified worldwide has increased greatly. Previous studies already defined generally high blastocyst cryo-survival rates after vitrification-warming (>95%), along with a positive correlation between blastocyst re-expansion and morphology with implantation. Additionally, artificial shrinkage has been outlined as a potentially beneficial procedure, while the association between embryo cryo-survival and trophectoderm biopsy is still unclear. Study design, size, duration Cohort study conducted at two IVF centers (1 and 2). A total of 2129 consecutive SETs using vitrified-warmed blastocysts in either non-PGT or PGT-A cycles between June 2016 and August 2017 were included. A freeze-all strategy was in place and three main pre-vitrification practices were used: (i) no biopsy and no artificial shrinkage (Clinic 1); (ii) trophectoderm biopsy and vitrification of collapsed blastocyst within 30 min (Clinics 1 and 2); and (iii) no biopsy but laser-assisted artificial shrinkage (Clinic 2). The primary outcome was the blastocyst degeneration rate. Overall, 2108 surviving blastocysts were graded at 1.5 h after warming for degeneration (absent or partial) and re-expansion (full, partial or absent) grades and post-warming morphological quality. Logistic regression analyses were conducted to assess the association of any pre-vitrification feature with blastocyst post-warming behavior. The logistic regressions conducted upon live birth after either untested or euploid SET also included the post-warming characteristics. Participants/materials, setting, methods Center 1 is a private IVF facility, while center 2 is the IVF facility of a University hospital. In non-PGT cycles, ICSI with blastocyst culture up to full-expansion and vitrification were performed. At center 1 the untested blastocysts were vitrified when still expanded, while at center 2 they underwent laser-assisted artificial shrinkage. In PGT-A cycles, in both clinics, trophectoderm biopsy (which involves laser-assisted shrinkage) was done without previous zona-opening on Day 3, and vitrification was performed within 30 min whilst the blastocyst remained collapsed. A qPCR-based chromosome analysis was conducted. Only SETs were performed (euploid-SET in case of PGT-A). Any cycle-, laboratory- and embryo-based feature which could impact blastocyst post-warming behavior was included in the analyses as putative confounder. Main results and the role of chance The overall degeneration rate was 1% (N = 21/2129). The results were consistent among different vitrification/warming operators or kits used, as well as any other IVF laboratory-related parameter. Blastocyst artificial shrinkage (either laser-assisted or biopsy-induced) involved a lower risk of degeneration after warming (odds ratio (OR) [95% CI] = 0.26 [0.09-0.79]). Conversely, both poor morphological quality pre-vitrification and taking 7 days to reach full blastulation resulted in a significantly higher risk (OR [95% CI] = 11.67 [3.42-39.83] and 4.43 [1.10-20.55], respectively). Importantly, trophectoderm biopsy did not show any association with blastocyst cryo-survival/degeneration. Overall 2.5% (N = 53/2108) blastocysts failed to re-expand post-warming. The only parameters significantly associated with no blastocyst re-expansion post-warming were average (OR [95% CI] = 4.96 [2.20-11.21]) or poor (OR [95% CI] = 19.54 [8.39-45.50]) morphological quality and taking 7 days to reach full blastulation (OR [95% CI] = 3.19 [1.23-8.29]), as well as prevention of spontaneous hatching pre-vitrification (OR [95% CI] = 0.10 [0.01-0.85]). The post-warming features of the survived blastocyst (i.e. degeneration and re-expansion scores and morphological quality) showed no significant association with vitrified blastocyst competence (i.e. live birth) when corrected for pre-vitrification ones (i.e. morphological quality, day of full development and, for untested SET, maternal age at oocyte retrieval). Of note, poor-quality blastocysts pre-vitrification showed a high overall cryo-survival rate post-warming 92.8% (N = 116/125), but the live birth rates were only 2.1% (N = 1/48) and 7.3% (N = 5/68) after untested and euploid SET, respectively. Limitations, reasons for caution This study is not randomized and the populations of patients undergoing either non-PGT or PGT-A cycles were different. Centers 1 and 2 adopted different pre-vitrification practices for non-biopsied blastocysts, according to their own laboratory policy. To this regard, multivariate logistic regression analyses were conducted for all outcomes under investigation. Wider implications of the findings Pre-vitrification features may be used to assist selection of competent embryos, moreover, these results allay concern that trophectoderm biopsy might be associated with impaired blastocyst quality or competence after vitrification/warming. Study funding/competing interest(s) None. Trial registration number None.

The effect of ICSI-related procedural timings and operators on the outcome

Abstract: STUDY QUESTION Do the ICSI-related procedural timings and operators affect the outcomes of an ART cycle? SUMMARY ANSWER The ICSI-related timings and operators do not associate with the mean blastulation rate per cohort of inseminated oocytes and the cumulative delivery rate per concluded cycle, except for a mild association between the times from induction of ovulation to oocyte denudation and the former outcome. WHAT IS KNOWN ALREADY In ART, specific timings, protocols and conditions must be complied with to preserve gamete developmental and reproductive competence during the required manipulations. ICSI represents a groundbreaking advancement that has been widely implemented. Nevertheless, the studies that examined the putative impact of ICSI-related procedural timings were mainly conducted in old-fashioned settings or in good prognosis patients. No report addressed issues like operators' skills and experience and uncertainties exist dealing with the effect of cumulus cells in the pre-incubation period in vitro before ICSI. However, all this information is crucial to efficiently plan the daily routine of an IVF lab, fill the existing gaps of knowledge and define proper key performance indicators. STUDY DESIGN, SIZE, DURATION Observational study conducted at a private IVF clinic (January 2016 to January 2018). We included all consecutive ICSI procedures (n = 1084 infertile couples undergoing 1444 cycles with or without preimplantation genetic testing (PGT); mean ± SD maternal age: 38.1 ± 4.0 years) with fresh autologous oocytes (n = 7999 oocytes, 5.5 ± 3.2 per treatment) inseminated with fresh non-donor ejaculated sperm. All operators and critical procedural timings (induction of ovulation to oocyte denudation, denudation and ICSI) were automatically recorded through an electronic witnessing system. The primary outcome measure was the cumulative delivery rate among both non-PGT and PGT-concluded cycles (i.e. delivery achieved or no supernumerary cryopreserved blastocyst available). The secondary outcome measure was the mean blastulation rate per cohort of inseminated oocytes. All confounders were registered and included in generalized linear models and multivariate logistic regression analyses. PARTICIPANTS/MATERIALS, SETTING, METHODS Fourteen and 12 operators were involved in denudation and ICSI procedures, respectively. Denudation was performed after 4.1 ± 1.2 h (2-7) of pre-incubation in vitro after oocyte retrieval, and ICSI was started immediately after. Beyond procedural timings and operators, all the putative confounders (patients' and cycles' characteristics) on the primary and/or secondary outcomes were systematically registered and included in the statistical analyses. MAIN RESULTS AND THE ROLE OF CHANCE The mean time from induction of ovulation to oocyte denudation was 39.3 ± 1.3 h. The mean procedural timings for denudation and ICSI were 8.1 ± 3.8 and 12.6 ± 6.4 min; both these variables were significantly dependent on the number of inseminated oocytes and the operators' skills and experience. The overall mean blastulation rate per cohort of inseminated oocytes was 34.0 ± 27.9%. This outcome was significantly associated with the time from induction of ovulation to oocyte denudation (mean blastulation rate stable in the time interval 38-42 h, but significantly higher for timings <38 h), maternal age (the mean blastulation rate drops especially beyond the age of 40 years) and categorized sperm concentration (highest mean blastulation rate for sperm concentrations ≥15 mil/ml and lowest for cryptozoospermic patients) through a generalized linear model that showed an adjusted r2 = 0.053 (P < 0.01). No association was found for denudation and ICSI timings and operators. Lastly, when adjusted for maternal age and number of inseminated oocytes, both ICSI-related procedural timings and operators did not associate with the cumulative delivery rate among both non-PGT- or PGT-concluded cycles. LIMITATIONS, REASONS FOR CAUTION This is a single private IVF center study. Its reproducibility should be assessed in different laboratory conditions, with different protocols and in the hands of different operators. Moreover, specific studies are warranted to address the beneficial/detrimental effect of the other putative confounders under investigation (e.g. kind of ovulation trigger, culture media, incubator, etc.). WIDER IMPLICATIONS OF THE FINDINGS Proactive communication between the embryologists and the clinicians might contribute to a reasoned and more efficient organization of the daily workload and increase the mean blastulation rate, especially when poor prognosis couples (advanced maternal age, reduced sperm count and/or ovarian reserve) are treated. STUDY FUNDING/COMPETING INTEREST(S) No funding. The authors declare no conflict of interest related to the present study.

Implementing PGD/PGD-A in IVF clinics: considerations for the best laboratory approach and management

Abstract: For an IVF clinic that wishes to implement preimplantation genetic diagnosis for monogenic diseases (PGD) and for aneuploidy testing (PGD-A), a global improvement is required through all the steps of an IVF treatment and patient care. At present, CCS (Comprehensive Chromosome Screening)-based trophectoderm (TE) biopsy has been demonstrated as a safe, accurate and reproducible approach to conduct PGD-A and possibly also PGD from the same biopsy. Key challenges in PGD/PGD-A implementation cover genetic and reproductive counselling, selection of the most efficient approach for blastocyst biopsy as well as of the best performing molecular technique to conduct CCS and monogenic disease analysis. Three different approaches for TE biopsy can be compared. However, among them, the application of TE biopsy approaches, entailing the zona opening when the expanded blastocyst stage is reached, represent the only biopsy methods suited with a totally undisturbed embryo culture strategy (time lapse-based incubation in a single media). Moreover, contemporary CCS technologies show a different spectrum of capabilities and limits that potentially impact the clinical outcomes, the management and the applicability of the PGD-A itself. In general, CCS approaches that avoid the use of whole genome amplification (WGA) can provide higher reliability of results with lower costs and turnaround time of analysis. The future perspectives are focused on the scrupulous and rigorous clinical validations of novel CCS methods based on targeted approaches that avoid the use of WGA, such as targeted next-generation sequencing technology, to further improve the throughput of analysis and the overall cost-effectiveness of PGD/PGD-A.

Assessment and management of the risk of SARS-CoV-2 infection in an IVF laboratory.

Abstract: Research Question To identify corrective measures aimed at reducing the risk of aerosol-mediated viral infection within an IVF laboratory Design A Failure Modes and Effect Analysis (FMEA) was conducted by a multidisciplinary IVF team A schematic representation of new protocols and procedures adopted during COVID-19 emergency has been defined, including directives about the behavior to adopt when entering the clinic and the laboratory, in case of face-to-face contact with patients and between staff members Lastly, the risk of cross-contamination between samples belonging to different patients during cell handling and manipulation has been also evaluated Potential failure modes for each phase have been analyzed, focusing on possible sources of error Risk priority numbers have been calculated as products of Occurrence x Severity x Detection scores Results Except for cell-cell contamination, which has been considered highly unlikely, failure modes during Patient-Staff, Staff-Staff and Staff-Cell interactions were estimated at moderate-high risk of infection The main corrective measures entailed precautionary logistic measures, the implementation of additional personal protective equipment (PPE), and changes in setting the IVF laboratory and scheduling the daily routine Some IVF procedures were also revised mainly aiming at increasing staff's awareness and caution during pandemic Conclusions Standard IVF laboratory protocols are insufficient to face a virus whose transmission is aerosol-mediated The measures outlined in this FMEA should thus be considered not only facing this pandemic but also for the future to be able to manage promptly any aerosol-mediated virus infection, whose impact on the management of an IVF laboratory might be less severe than COVID-19 although not completely negligible (ie staff reduction and patient health at the time of IVF procedure)

Impact of Maternal Age on Oocyte and Embryo Competence

Abstract: The overall success of human reproduction, either spontaneously or after IVF, is highly dependent upon maternal age. The main reasons for age-related infertility include reduced ovarian reserve and decreased oocyte/embryo competence due to aging insults, especially concerning an increased incidence of aneuploidies and possibly decreased mitochondrial activity. Age-related chromosomal abnormalities mainly arise because of meiotic impairments during oogenesis, following flawed chromosome segregation patterns such as non-disjunction, premature separation of sister chromatids, or the recent reverse segregation. In this review, we briefly discuss the main mechanisms putatively impaired by aging in the oocytes and the deriving embryos. We also report the main strategies proposed to improve the management of advanced maternal age women in IVF: fertility preservation through oocyte cryopreservation to prevent aging; optimization of the ovarian stimulation and enhancement of embryo selection to limit its effects; and oocyte donation to circumvent its consequences.

Advanced Maternal Age in IVF: Still a Challenge? The Present and the Future of Its Treatment.

Abstract: Advanced maternal age (AMA; >35 year) is associated with a decline in both ovarian reserve and oocyte competence. At present, no remedies are available to counteract the aging-related fertility decay, however different therapeutic approaches can be offered to women older than 35 year undergoing IVF. This review summarizes the main current strategies proposed for the treatment of AMA: (i) oocyte cryopreservation to conduct fertility preservation for medical reasons or "social freezing" for non-medical reasons, (ii) personalized controlled ovarian stimulation to maximize the exploitation of the ovarian reserve in each patient, (iii) enhancement of embryo selection via blastocyst-stage preimplantation genetic testing for aneuploidies and frozen single embryo transfer, or (iv) oocyte donation in case of minimal/null residual chance of pregnancy. Future strategies and tools are in the pipeline that might minimize the risks of AMA through non-invasive approaches for embryo selection (e.g., molecular analyses of leftover products of IVF, such as spent culture media). These are yet challenging but potentially ground-breaking perspectives promising a lower clinical workload with a higher cost-effectiveness. We also reviewed emerging experimental therapeutic approaches to attempt at restoring maternal reproductive potential, e.g., spindle-chromosomal complex, pronuclear or mitochondrial transfer, and chromosome therapy. In vitro generation of gametes is also an intriguing challenge for the future. Lastly, since infertility is a social issue, social campaigns, and education among future generations are desirable to promote the awareness of the impact of age and lifestyle habits upon fertility. This should be a duty of the clinical operators in this field.

Dynamics and clinical relevance of maternal mRNA clearance during the oocyte-to-embryo transition in humans.

Abstract: Maternal mRNA clearance is an essential process that occurs during maternal-to-zygotic transition (MZT). However, the dynamics, functional importance, and pathological relevance of maternal mRNA decay in human preimplantation embryos have not yet been analyzed. Here we report the zygotic genome activation (ZGA)-dependent and -independent maternal mRNA clearance processes during human MZT and demonstrate that subgroups of human maternal transcripts are sequentially removed by maternal (M)- and zygotic (Z)-decay pathways before and after ZGA. Key factors regulating M-decay and Z-decay pathways in mouse have similar expression pattern during human MZT, suggesting that YAP1-TEAD4 transcription activators, TUT4/7-mediated mRNA 3'-oligouridylation, and BTG4/CCR4-NOT-induced mRNA deadenylation may also be involved in the regulation of human maternal mRNA stability. Decreased expression of these factors and abnormal accumulation of maternal transcripts are observed in the development-arrested embryos of patients who seek assisted reproduction. Defects of M-decay and Z-decay are detected with high incidence in embryos that are arrested at the zygote and 8-cell stages, respectively. In addition, M-decay is not found to be affected by maternal TUBB8 mutations, although these mutations cause meiotic cell division defects and zygotic arrest, which indicates that mRNA decay is regulated independent of meiotic spindle assembly. Considering the correlations between maternal mRNA decay defects and early developmental arrest of in vitro fertilized human embryos, M-decay and Z-decay pathway activities may contribute to the developmental potential of human preimplantation embryos.

The POSEIDON Criteria and Its Measure of Success Through the Eyes of Clinicians and Embryologists.

Abstract: This article represents a viewpoint on the POSEIDON criteria by a group of clinicians and embryologists. Its primary objective is to contextualize the Poseidon criteria and their metric of success for the relevant Frontiers Research Topic "POSEIDON's Stratification of Low Prognosis Patients in ART: The WHY, the WHAT, and the HOW". "Low prognosis" relates with reduced oocyte number, which can be associated with low or sometimes a normal ovarian reserve and is aggravated by advanced female age. These aspects will ultimately affect the number of embryos generated and consequently, the cumulative live birth rate. The novel system relies on female age, ovarian reserve markers, ovarian sensitivity to exogenous gonadotropin, and the number of oocytes retrieved, which will both identify the patients with low prognosis and stratify such patients into one of four groups of women with "expected" or "unexpected" impaired ovarian response to exogenous gonadotropin stimulation. Furthermore, the POSEIDON group introduced a new measure of clinical success in ART, namely, the ability to retrieve the number of oocytes needed to obtain at least one euploid blastocyst for transfer in each patient. Using the POSEIDON criteria, the clinician can firstly identify and classify patients who have low prognosis in ART, and secondly, aim at designing an individualized treatment plan to maximize the chances of achieving the POSEIDON measure of success in each of the four low prognosis groups. The novel POSEIDON classification system is anticipated to improve counseling and management of low prognosis patients undergoing ART, with an expected positive effect on reproductive success and a reduction in the time to live birth.