Clinical pregnancy rate following frozen embryo transfer is higher with blastocysts vitrified on day 5 than on day 6.

PURPOSE: The aim of this study was to compare the pregnancy rates between good quality blastocysts vitrified on day 6 versus blastocysts vitrified on day 5 after fertilization. METHODS: This is a retrospective cohort study of 791 freeze-thaw cycles of blastocysts vitrified either on day 5 or on day 6 and transferred between January 2012 and October 2015. Five hundred and thirty-seven cycles included blastocysts vitrified on day 5, and 254 cycles included blastocysts vitrified on day 6. RESULTS: The age of the patients and the proportion of embryos that survived the thawing process were comparable between the two groups. More good quality embryos were transferred in the group in which blastocysts were vitrified on day 6 (1.2 vs. 1.3, p = 0.005), but the clinical pregnancy rate (44 vs. 33 %, p = 0.002) and the ongoing pregnancy rate (41 vs. 28 %, p < 0.001) were higher in the group in which blastocysts were vitrified on day 5. Multivariate regression analysis adjusting for patient's age, number of good quality embryos transferred (≥3BB), and treatment protocol demonstrated that the day 6 vitrified group had a significantly lower clinical pregnancy rate compared to the day 5 vitrified group (OR 0.54, 95 % CI 0.38-0.76). CONCLUSIONS: The clinical pregnancy rate following frozen embryo transfer is significantly lower with blastocysts vitrified on day 6 compared to blastocysts vitrified on day 5.

Improving IVF Utilization with Patient-Centric Artificial Intelligence-Machine Learning (AI/ML): A Retrospective Multicenter Experience.

Objectives: In vitro fertilization (IVF) has the potential to give babies to millions more people globally, yet it continues to be underutilized. We established a globally applicable and locally adaptable IVF prognostics report and framework to support patient-provider counseling and enable validated, data-driven treatment decisions. This study investigates the IVF utilization rates associated with the usage of machine learning, center-specific (MLCS) prognostic reports (the Univfy® report) in provider-patient pre-treatment and IVF counseling. Methods: We used a retrospective cohort comprising 24,238 patients with new patient visits (NPV) from 2016 to 2022 across seven fertility centers in 17 locations in seven US states and Ontario, Canada. We tested the association of Univfy report usage and first intra-uterine insemination (IUI) and/or first IVF usage (a.k.a. conversion) within 180 days, 360 days, and "Ever" of NPV as primary outcomes. Results: Univfy report usage was associated with higher direct IVF conversion (without prior IUI), with odds ratios (OR) 3.13 (95% CI 2.83, 3.46), 2.89 (95% CI 2.63, 3.17), and 2.04 (95% CI 1.90, 2.20) and total IVF conversion (with or without prior IUI), OR 3.41 (95% CI 3.09, 3.75), 3.81 (95% CI 3.49, 4.16), and 2.78 (95% CI 2.59, 2.98) in 180-day, 360-day, and Ever analyses, respectively; p < 0.05. Among patients with Univfy report usage, after accounting for center as a factor, older age was a small yet independent predictor of IVF conversion. Conclusions: Usage of a patient-centric, MLCS-based prognostics report was associated with increased IVF conversion among new fertility patients. Further research to study factors influencing treatment decision making and real-world optimization of patient-centric workflows utilizing the MLCS reports is warranted.

Binucleated and micronucleated blastomeres in embryos derived from human assisted reproduction cycles.

This prospective sequential, cohort study examined the two most common multinucleation phenotypes observed in the authors' clinic, binucleated (BN) and micronucleated (MN) blastomeres, and included all intracytoplasmic sperm injection (ICSI) patients <40 years of age with at least one multinucleated embryo in the cohort as observed on day 2 of development. Eighty ICSI cycles of 560 consecutive cycles had multinucleated embryos (14.3%). Of the 80 cycles, 770 embryos were derived; 183 (23.8%) were observed to be multinucleated. Blastocyst rates were significantly higher with BN than MN embryos. MN embryos were more often derived from embryos with poor pronuclear morphology (41/81 = 50.6%). Transferred mononucleated sibling embryos from the BN group had an ongoing pregnancy rate of 48% (12/25) compared with 15.4% (4/26 from the group with MN embryos (P = 0.03). The implantation rate for sibling embryos from the BN group was higher than for those from the MN group. Fluorescence in-situ hybridization (FISH) analysis showed that BN embryos had normal blastomeres significantly more frequently than MN embryos (9/28 (32.1%) versus 1/27 (3.7%), P = 0.016). Time-lapse photography showed that the nuclei of both morphologies dissolved independently before the next mitotic division and that BN blastomeres definitely have two distinct nuclei. These observations indicate two diverse morphologies and causal mechanisms. Time-lapse photography showed that both were subject to independent dissolution of their nuclear membrane suggesting an asynchrony between the nuclei and a possible interruption in proper nuclear and cell division. Multinucleation should definitely be looked for during IVF assessment. Excluding these embryos from transfer is prudent practice.