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Purpose/study question: Does piercing oocyte membranes during ICSI allow the influx of surrounding zwitterionic buffer into human oocytes and result in altered developmental competence? Methods: Human oocytes directed to IRB-approved research were used to determine the unrestricted influx of surrounding buffer into the oocyte after piercing of membranes via confocal fluorescence microscopy (n = 80 human MII oocytes) and the influence of the select buffer influx of HEPES, MOPS, and bicarbonate buffer on the oocyte transcriptome using ultra-low input RNA sequencing (n = 40 human MII oocytes). Results: Piercing membranes of human MII oocytes during sham-ICSI resulted in the unrestricted influx of surrounding culture buffer into the oocyte that was beyond technician control. Transcriptome analysis revealed statistically significant decreased cytoskeletal transcripts in the pierced buffer cohorts, higher levels of embryo competency transcripts (IGF2 and G6PD) in the bicarbonate buffer cohort, higher levels of stress-induced transcriptional repressor transcripts (MAF1) in the HEPES and MOPS cohorts, and decreased levels of numerous chromosomal maintenance transcripts (SMC3) in the HEPES buffer cohort. The HEPES buffer cohort also revealed higher levels of transcripts suggesting increased oxidative (GPX1) and lysosomal stress (LAMP1). Conclusion: The influence of zwitterionic buffer on intrinsic cellular mechanisms provides numerous concerns for their use in IVF clinical applications. The primary concern is the ICSI procedure, in which the surrounding buffer is allowed influx into the oocytes after membrane piercing. Selecting a physiological bicarbonate buffer may reduce imposed stress on oocytes, resulting in improved embryo development and clinical results because intracellular MOPS, and especially HEPES, may negatively impact intrinsic biological mechanisms, as revealed by transcriptome changes. These findings further support the utilization of bicarbonate buffer as the oocyte-holding medium during ICSI. [ABSTRACT FROM AUTHOR]

Context: Our center’s quality improvement optimization process on many occasions anecdotally suggested that oocyte assessments might enhance embryo assessment in predicting pregnancy chances with in vitro fertilization (IVF). Objective: To prospectively compare a morphologic oocyte grading system to standard day-3 morphologic embryo assessment. Design, Setting, Patients: We prospectively investigated in a private academically-affiliated infertility center 94 consecutive IVF cycles based on 6 criteria for oocyte quality: morphology, cytoplasm, perivitelline space (PVS), zona pellucida (ZP), polar body (PB) and oocyte size, each assigned a value of -1 (worst), 0 (average) or +1 (best), so establishing an average total oocyte score (TOS). Embryo assessment utilized grade and cell numbers of each embryo on day-3 after oocyte retrieval. Clinical pregnancy was defined by presence of at least one intrauterine gestational sac. Interventions: Standard IVF cycles in infertile women. Main Outcome Measures: Predictability of pregnancy based on oocyte and embryo-grading systems. Results: Average age for all patients was 36.5 ± 7.3 years; mean oocyte yield was 7.97± 5.76; Patient specific total oocyte score (PTOS) was -1.05 ± 2.24. PTOS, adjusted for patient age, was directly related to odds of increased embryo cell numbers (OR 1.12, P = 0.025), embryo grade (OR 1.19, P < 0.001) and clinical pregnancy [OR 1.58 (95%CI 1.23 to 2.02), P < 0.001]. Restricting the analysis to day three embryos of high quality (8-cell/ good grades), TOS was still predictive of clinical pregnancy (OR 2.08 (95%CI 1.26 to 3.44, P = 0.004). Among the 69 patients with embryos of Grade 4 or better available for transfer 23 achieved Clinical Pregnancy. When the analysis was restricted to the 69 transfers with good quality embryos (≥ Grade 4) the Oocyte Scoring System (TOS) (AUC±SE 0.863±0.044, oocyte score) provided significantly greater predictive value for clinical pregnancy compared to the embryo grade alone (AUC 0.646 ± 0.072, embryo grade) p = 0.015. Conclusions: Oocyte-scoring, thus, provides useful clinical information especially in good prognosis patients with large numbers of high quality embryos. This finding appears of particular importance at a time when many IVF centers are committing sizable investments to closed incubation systems with time-lapse photography, which are exclusively meant to define embryo morphology. [ABSTRACT FROM AUTHOR]

Objectives: To examine the effect of polycystic ovary syndrome (PCOS), a marker of the metabolic syndrome, on selected indicators of in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment success. Methods: A retrospective cohort study was conducted using existing data on 69 IVF/ICSI treatment cycles undergone by PCOS women and a caliper-matched sample of 69 IVF/ICSI treatment cycles undergone by non-PCOS women over a 7-year period at a major fertility treatment center. Matching criteria were age and date at IVF/ICSI treatment initiation. Process and outcome measures were used to define successful IVF/ICSI treatment. Statistical significance was determined at an alpha level of 0.05. Results: The total number of oocytes and the number of immature oocytes retrieved in the process of an IVF/ICSI cycle were significantly higher in the context of PCOS. No significant differences were observed among PCOS and non-PCOS groups on various IVF/ICSI cycle outcomes, including high-grade embryo, pregnancy achievement, miscarriage, and live birth status. Conclusions: Although IVF/ICSI yields more oocytes in the context of PCOS, IVF/ICSI outcomes do not differ significantly by PCOS status. Prospective cohort studies are needed to examine short-term and long-term health effects of PCOS in the context of IVF/ICSI. [ABSTRACT FROM AUTHOR]