[Successful clinical pregnancy of cryopreserved human oocytes after vitrification]

To assess the feasibility and clinical value of cryopreservation of human oocytes.

Human oocytes were collected during stimulated cycle and then vitrificated with cryoloop. Surviving oocytes were thawed and then inseminated by intracytoplasmic sperm injection (ICSI). The fertilized oocytes were further cultured in vitro for 48 - 72 hours. High-quality embryos were transferred to the patients of infertility with informed consent.

A total of 235 oocytes were vitrificated and thawed. The survival and fertilization rates of the oocytes were 71.9% and 72.5% respectively. Forty-one embryos were transferred to 11 patients. Two of the 11 patients achieved pregnancy, one of which gave birth of 2 healthy female twin babies and the other was at the 16 th week of pregnancy. The mother and babies were all healthy.

Human oocyte vitrification is safe and feasible.