Ovulation is the moment an ovary releases an egg ready for fertilization. This begins the luteal phase of the menstrual cycle. The luteal phase ends with a menstrual period unless pregnancy occurs.

To ensure the correct euploid state of embryos, it is essential that vertebrate oocytes await fertilization arrested at metaphase of meiosis II. This MII arrest is mediated by XErp1/Emi2, which ...

Figure 1: Overview of the imprinted domain in human 15q11–q13 and the PWS family studied. We isolated mouse oocytes following hormonal stimulation as described 19. We isolated mouse spermatozoa ...