Cell Journal (Jan 2011)
In Vitro Maturation of Germinal Vesicle Oocytes in Stimulated Intracytoplasmic Sperm Injection Cycles
Abstract
Objective: This study evaluated in vitro maturation (IVM) of oocytes in the germinal vesicle(GV) stage in stimulated intracytoplasmic sperm injection (ICSI) cycles.Materials and Methods: A total of 26 women, aged 18 -37 years, who were candidatesfor ICSI at the Fatemeh Zahra Infertility and Health Reproductive Research Center in 2007were recruited for this study. We used the standard long protocol for ovarian stimulation.Follicles >11 mm were punctured 36-38 hours after administration of 10000 IU humanchorionic gonadotrophin (hCG). Immature oocytes were cultured for 24-30 hours. Oocytesthat liberated polar bodies were injected by sperm prepared within the previous day. IVMfertilized oocytes were cultured an additional 24-30 hours for cleavage. The rates of maturation,fertilization and cleavage in IVM oocytes were recorded and statistically comparedto in vivo matured sibling oocytes.Results: There were 279 collected oocytes (mean±SD: 10.73 ± 6.2), of which 4.08±2.79were subjected to IVM. An average of 2.73 ± 2.15 GV oocytes (70%) developed to metaphaseII (MII). Although the maturation rate significantly differed between the IVM and invivo MII sibling oocyte groups (p=0.027), the numbers of fertilized oocytes (p=0.795) andcleaved embryos (p=0.529) were not significantly high in the in vivo group. Transfer of IVMembryos occurred in only three cases with one pregnancy that resulted in the delivery ofa healthy baby.Conclusion: This study shows that culturing GV oocytes can produce acceptable numbersof four-cell embryos on the transfer day. The developmental competence of oocytesis not significantly different between early stage IVM and in vivo sibling embryos.
