PURPOSE: To determine if the removal of cytoplasm from metaphase II human donor oocytes damages the meiotic spindle apparatus. MATERIALS AND METHODS: Cryopreservation of metaphase II human oocytes was performed using a fast-freeze, fast-thaw protocol. Upon thaw, oocytes were incubated for 3-4 h and then used for cytoplasmic donation (test oocytes). Oocytes thawed but not used for donation served as controls. Test and control oocytes were fixed using a microtubule-stabilizing buffer. Tubulin was localized using antitubulin monoclonal antibody. Chromosomes were identified by counterstaining with DAPI. RESULTS: Forty-four oocytes had cytoplasm removed (test group) while 12 were not used for the procedure (controls). Twenty-three oocytes survived the donation procedure. Rates of normal spindle structure for the control and test groups were 21/23 (91.3%) and 12/12 (100%), respectively. CONCLUSION: The removal of cytoplasm from a metaphase II human donor oocyte does not appear to significantly increase the damage to chromosome alignment or to the spindle structure.
PURPOSE: To determine if the removal of cytoplasm from metaphase II humandonor oocytes damages the meiotic spindle apparatus. MATERIALS AND METHODS: Cryopreservation of metaphase II human oocytes was performed using a fast-freeze, fast-thaw protocol. Upon thaw, oocytes were incubated for 3-4 h and then used for cytoplasmic donation (test oocytes). Oocytes thawed but not used for donation served as controls. Test and control oocytes were fixed using a microtubule-stabilizing buffer. Tubulin was localized using antitubulin monoclonal antibody. Chromosomes were identified by counterstaining with DAPI. RESULTS: Forty-four oocytes had cytoplasm removed (test group) while 12 were not used for the procedure (controls). Twenty-three oocytes survived the donation procedure. Rates of normal spindle structure for the control and test groups were 21/23 (91.3%) and 12/12 (100%), respectively. CONCLUSION: The removal of cytoplasm from a metaphase II humandonor oocyte does not appear to significantly increase the damage to chromosome alignment or to the spindle structure.