OocytesOvaryOogenesisOocyte DonationOocyte RetrievalXenopus laevisMeiosisIn Vitro Oocyte Maturation TechniquesXenopusMicroinjectionsFertilizationMetaphaseCumulus CellsParthenogenesisBlastocystOvumSperm-Ovum InteractionsCryopreservationSperm Injections, IntracytoplasmicEmbryonic DevelopmentEmbryo TransferZona PellucidaMaturation-Promoting FactorSpermatozoaZygoteCleavage Stage, OvumEmbryo Culture TechniquesRNA, ComplementaryPregnancyEgg ProteinsNuclear Transfer TechniquesFollicular FluidOvulation InductionCytoplasmProto-Oncogene Proteins c-mosCryoprotective AgentsVitrificationCell NucleusPolar BodiesEmbryo, MammalianRNA, MessengerEmbryonic and Fetal DevelopmentPregnancy Rate