The impact of follicle-flushing during oocyte collection on embryo development of in-vitro fertilization.

Background: To evaluate the impact of follicle-flushing during oocyte collection on embryo development potential retrospectively.

Methods: A total of 1714 cases, including 133 who experienced retrieval difficulty (repeated follicle-flushing) on the day of oocyte retrieval (difficulty group) and the control 1581 cases (control group), were assessed in this retrospective study. The number of oocytes recovered, two pro-nuclei fertilization (2PN-fertilization), day 3 good-quality embryo and day 5/6 blastocyst utilization rates were compared between the difficulty group and control group correspondingly.

Deletion of maternal UHRF1 severely reduces mouse oocyte quality and causes developmental defects in preimplantation embryos.

The ubiquitin-like, containing PHD and RING finger domains, 1 (UHRF1) protein recognizes DNA methylation and histone modification and plays a critical role in epigenetic regulation. Recently, UHRF1 was shown to have a role in DNA methylation in oocytes and early embryos. Here, we reveal that maternal UHRF1 determines the quality of mouse oocytes.