Advances in imprinted DNA methylation of in vitro culture of immature oocytes

In vitro maturation (IVM) of oocytes, a frontier technique in in vitro fertilization (IVF) field, specifically targeting at some infertile patients with egg maturation disorders, have been introduced into the clinical assisted reproductive technology. It is a mild approach to replace conventional ovarian stimulation for polycystic ovary syndrome (PCOS) patients and has advantages of reducing the burden and cost of treatment. However, it is noteworthy that oocyte culture may interfere with epigenetic reprogramming of the development process, leading to birth defects in the offspring. This review will talk about impression of IVM on expression of imprinted genes, early embryonic development and imprinted gene methylation and impression of embryo culture on the methylation. Key words: In vitro maturation; Assisted reproduction; Imprinted gene; DNA methylation