IVF is the common name for the in vitro fertilization-embryo transfer technique, a process in which eggs and sperm are removed separately, placed in culture to fertilize them, and then the embryos are transferred back into the mother’s uterus to develop into a fetus. Since not every egg can be fertilized and not every fertilized egg can develop into a viable embryo, multiple eggs have to be obtained from the woman’s body to ensure that there are embryos that can be transferred, which requires ovulation treatment for the woman. In ovulation promotion, the internal factors that affect egg quality are the age of the patient, the cause of infertility and ovarian reserve. External factors of egg quality include excessive ovarian stimulation that may compromise egg quality. Assessment of egg quality in the clinic The quality of eggs is usually determined by estrogen, for example, a mature follicle corresponding to >200-300 pg/ml of estrogen, if the estrogen is below 200 pg/ml, the egg quality may be poor. Assessment of egg quality in the embryo culture room For the quality of eggs is again a different assessment method. The maturation of the oocyte consists mainly of the maturation of the nucleus and the maturation of the cytoplasm. The maturation of the oocyte nucleus is announced when a gap appears between the oocyte and the zona pellucida and the first polar body is released in the perivitelline space, i.e. the oocyte enters the MII stage. After maturation of the cytoplasm the oocyte shows the morphological characteristics of sparse arrangement of granulosa cells and translucent radial crown. The mature cytoplasm should be clear and structurally homogeneous with uniformly clear granules inside. The oocyte-radiolar crown morphology was classified into four grades according to the number of oocytes and the degree of expansion. Grade I is the GV stage, grade II is the MI stage, and grades III to IV are the MII stage; the higher the grade, the higher the maturity of the oocyte.