[Interest of iDAScore (intelligent Data Analysis Score) for embryo selection in routine IVF laboratory practice: Results of a preliminary study]. / Intérêt de l'iDAScore (intelligent Data Analysis Score) dans la pratique quotidienne d'un laboratoire de FIV pour la sélection embryonnaire : résultats d'une étude préliminaire.

INTRODUCTION: Embryo selection is a major challenge in ART, especially since the generalization of single embryo transfer, and its optimization could lead to the improvement of clinical results in IVF. Recently, several Artificial Intelligence (AI) models, based on deep-learning such as iDAScore, have been developed. These models, trained on time-lapse videos of embryos with known implantation data, can predict the probability of pregnancy for a given embryo, allowing automatization and standardization in embryo selection. MATERIAL AND METHODS: In this study, we have compared the hierarchical categorization of 311 D5 blastocysts of iDAScore v1.0 and the embryologists of our unit. These 311 D5 blastocysts have been classified as top (70.1%), good (Q+: 10.6%) and poor (Q-: 19.3%) quality by embryologists according to Gardner classification. Median iDAScores were [9.9-8.4],]8.4-7.5] and]7.5-2.1] for top, good and poor-quality blastocysts respectively. RESULTS: We observed a significantly concordant categorization between iDAScore and embryologists for top, good and poor-quality blastocysts (respectively, 89.5, 36.4 and 48.3%, P < 10-4). Moreover, the hierarchical categorization of the three best blastocysts between iDAScore and the embryologists was as follow: 1st rank: 71.9%; 2nd rank: 61.6%; 3rd rank: 56.8% (P=0.07). One hundred and fifty-one blastocysts with known implantation data were analyzed. The iDAScore of blastocysts that implanted was significantly higher than those that did not implant (implantation+: 9.10±0.57; implantation-: 8.70±0.95, P=0.003). CONCLUSION: This preliminary study shows that iDAScore is able to perform a reproducible, reliable and immediate hierarchical classification of blastocysts. Moreover, this tool can identify the blastocysts with the highest implantation potential. If these results confirmed on a larger scale of embryos and patients, IA could revolutionize IVF laboratories by standardizing embryo hierarchical selection.

Impact of oxygen tension according to embryo stage of development: a prospective randomized study.

Human embryo culture under 2-8% O2 is recommended by ESHRE revised guidelines for good practices in IVF labs. Nevertheless, notably due to the higher costs of embryo culture under hypoxia, some laboratories perform embryo culture under atmospheric O2 tension (around 20%). Furthermore, recent meta-analyses concluded with low evidence to a superiority of hypoxia on IVF/ICSI outcomes. Interestingly, a study on mice embryos suggested that oxidative stress (OS) might only have an adverse impact on embryos at cleavage stage. Hence, we aimed to demonstrate for the first time in human embryos that OS has a negative impact only at cleavage stage and that sequential culture conditions (5% O2 from Day 0 to Day 2/3, then «conventional¼ conditions at 20% O2 until blastocyst stage) might be a valuable option for human embryo culture. 773 IVF/ICSI cycles were included in this randomized clinical trial from January 2016 to April 2018. At Day 0 (D0), patients were randomized using a 1:2 allocation ratio between group A (20% O2; n = 265) and group B (5% O2; n = 508). Extended culture (EC) was performed when ≥ 5 Day 2-good-quality-embryos were available (n = 88 in group A (20% O2)). In subgroup B, 195 EC cycles were randomized again at Day 2 (using 1:1 ratio) into groups B' (5% O2 until Day 6 (n = 101)) or C (switch to 20% O2 from Day 2 to Day 6 (n = 94). Fertilization rate, cleavage-stage quality Day 2-top-quality-embryo (D2-TQE), blastocyst quality (Day 5-top-quality-blastocyst (D5-TQB) and implantation rate (IR) were compared between groups A and B (= cleavage-stage analysis), or A(20% O2), B'(5% O2) and C(5%-to-20% O2). Overall, characteristics were similar between groups A and B. Significantly higher rates of early-cleaved embryos, top-quality and good-quality embryos on Day 2 were obtained in group B compared to group A (P < 0.05). This association between oxygen tension and embryo quality at D2 was confirmed using an adjusted model (P < 0.05). Regarding blastocyst quality, culture under 20% O2 from Day 0 to Day 6 (group A) resulted in significantly lower Day 5-TQB number and rates (P < 0.05) compared to both groups B' and C. Furthermore, blastocyst quality was statistically equivalent between groups B' and C (P = 0.45). At Day 6, TQB numbers and rates were also significantly higher in groups B' and C compared to group A (P < 0.05). These results were confirmed analyzing adjusted mean differences for number of Day 5 and Day 6 top quality embryos obtained in group A when compared to those respectively in groups B' and C (P < 0.05). No difference in clinical outcomes following blastocyst transfers was observed. These results would encourage to systematically culture embryos under hypoxia at least during early development stages, since OS might be detrimental exclusively before embryonic genome activation.

[Impact of the type of incubator (non-humidified versus humidified) on embryo culture media osmolality]. / Impact du type d'incubateur (atmosphère humidifiée versus sec) sur l'osmolalité des milieux de culture embryonnaire.

INTRODUCTION: Benchtop incubators with small individual chambers have been developed in order to improve the stability of embryo culture conditions reducing the environmental stress during the embryo development. These new dry incubators were designed without any air humidification system in order to prevent bacterial proliferation and to enable the use of time-lapse system. However, an elevated evaporation of the culture media could occur in these conditions. The main objective of the study is to analyse the impact of the used incubator type on the embryo culture media osmolality. MATERIALS AND METHODS: Microdrops of 50µL of culture media were placed in 60mm diameter culture dishes, and quickly covered with either 7 or 8mL of mineral oil in an IVF workstation with laminar airflow. Two series of culture dishes have been randomly placed either in a humidified incubator or in a dry benchtop incubator. The microdrops of each culture dishes were sampled at D0, D1, D2, D3, and D5 respectively to measure the osmolality in triplicate using a cryoscopic osmometer. The mean values of osmolality in each incubator have been compared respectively on D0, D1, D2, D3 and D5 with appropriate statistical tests, and considered statistically significant when P<0.05. RESULTS: The osmolality of the microdrops placed in the dry benchtop incubator differed significantly after the third day of culture, regardless of the level of mineral oil in the culture dishes. Indeed, using Petri dishes covered respectively with 7 or 8mL of mineral oil, osmolality values of samples from the dry incubator were significantly higher than those from the humidified one, at D3 and D5 (D3/7mL: 273±2.1 vs. 268±1.0mOsm/kg; P=0.02; D3/8mL: 282±8.0 vs. 270±0.7mOsm/kg; P=0.04) and D5 (D5/7mL: 283±1.5 vs. 270±3.6mOsm/kg; P=0.004; D5/8mL: 287±5.6 vs. 268±2.3mOsm/kg; P=0.005). Furthermore, the analysis on paired samples showed that the osmolality in the dry benchtop incubator at D5 using 7mL of oil (283±1.5mOsm/kg; P=0.003) and at D3 (273±2.1mOsm/kg; P=0.016) and D5 (287±5.6mOsm/kg; P=0.009) using 8mL of oil was significantly higher than that measured at D0 (265±1.9mOsm/kg). CONCLUSION: A significant increase of the embryo culture media osmolality was observed in the dry benchtop incubator with ambient hygrometry in our standard conditions. Adding 1mL of oil was not sufficient to reduce the evaporation of the media. Although maintained at a physiological level, the impact of the osmolality changes on the in vitro embryo development has to be further determined.

[Dual trigger with gonadotropin-releasing hormone agonist and hCG to improve oocyte maturation rate]. / Intérêt du double déclenchement par agoniste de la GnRH et hCG en cas d'antécédent d'immaturité ovocytaire en FIV/ICSI.

OBJECTIVE: This study investigates dual trigger with GnRHa and hCG as a potential treatment in patients with a history of ≥25 % immature oocytes retrieved in IVF/ICSI cycles. METHODS: This is a retrospective case-control study performed between October 2008 and December 2017. Forty-seven patients who experienced high oocyte immaturity rate (≥25 %) during their first IVF/ICSI cycle (analyzed as control group) and received a dual trigger for their subsequent cycle, were involved. During dual trigger cycles, patients received antagonist protocol and ovulation triggering using triptorelin 0.2mg and hCG. Primary endpoint was maturation rate (MR). Secondary endpoints were fertilization, D2 top quality embryo (TQE) rates, clinical pregnancy rate per fresh embryo transfer and cumulative clinical pregnancy rate per couple. RESULTS: A significant increase in MR was achieved in case of dual trigger (71.0 %) when compared to control group (47.8 %; P<0.0001). Moreover, cumulative clinical pregnancy rate yielded 46.8 % in dual trigger group, which was statistically higher than 27.6 % obtained in control group (P=0.05). However, fertilization, D2 TQE rates and clinical pregnancy rates/transfer were statistically similar when compared between the two groups. CONCLUSION: Dual trigger seems efficient for managing patients with high oocyte immaturity rate.

[A prospective study to compare the efficiency of oocyte vitrification using closed or open devices]. / Étude prospective comparant l'efficacité de la vitrification ovocytaire en système fermé ou en système ouvert.

OBJECTIVES: Oocyte vitrification using an open device is thought to be a source of microbiological and chemical contaminations that can be avoided using a closed device. The principal purpose of this study was to compare the two vitrification protocols: closed and open system. The secondary aim was to study the effects of the storage in the vapor phase of nitrogen (VPN) on oocytes vitrified using an open system and to compare it to those of a storage in liquid nitrogen (LN). METHODS: Forty-four patients have been included in our study between November 2014 and May 2015. Two hundred and fourteen oocytes have been vitrified at germinal vesicle (GV), metaphase I (0PB) and metaphase II (1PB) stages. We vitrified 96 oocytes (59 GV/37 0PB) using a closed vitrification device and 118 oocytes (57 GV/31 0PB/30 1PB) using an open device. The vitrified oocytes were then stored either in LN or in VPN. The main outcome measures were the survival rate after warming (SR), meiosis resumption rate (MRR) and maturation rate (MR). RESULTS: The global post-thaw SR was significantly higher for oocytes vitrified using an open system (93.2%) compared to those vitrified using a closed one (64.5%; P<0.001). On the contrary, there was no significant difference in terms of global MRR and MR (82.1% vs. 87.5% and 60.7% vs. 61.2% using closed and open system respectively). The SR, MRR and the MR were not significantly different when vitrified oocytes were stored in VPN or LN (91.6, 83.8, 64.5% vs. 93.9, 89.8, 59.1% respectively). CONCLUSION: Taking into account the limits of our protocol, the open vitrification system remains the more efficient system. The use of sterile liquid nitrogen for oocyte vitrification and the subsequent storage in vapor phase of nitrogen could minimize the hypothetical risks of biological and chemical contaminations.