Faculty Bibliography

OBJECTIVE: To report our oocyte cryopreservation (OC) outcomes including meiotic spindle (MS) evaluation of metaphase II (MII) oocytes destined for OC and thaw. DESIGN: Retrospective. SETTING: University-based infertility center. PATIENT(S): Women attempting pregnancy using cryopreserved oocytes. INTERVENTION(S): OC, MS evaluation. MAIN OUTCOME MEASURE(S): Survival, two pronuclear (2PN) fertilization, achieving embryo quality suitable for transfer or refreezing, blastocyst formation. RESULT(S): Thirty-two OC-thaw cycles resulted in 20 pregnancies, 18 either ongoing or delivered. In 26 cycles, MS evaluation was performed: 262/303 (86%) thawed/recovered oocytes survived, 218/262 (83%) achieved 2PN fertilization, 133/218 (61%) became suitable for day-3 and 122/218 (56%) for day-5 transfer. In total, 58 embryos were transferred resulting in a 62% pregnancy and a 41% implantation rate. Of oocytes evaluated before cryopreservation, 247 (82%) were spindle-positive; 96% of these were also spindle-positive after thawing. Blastocyst formation and suitability for day-5 transfer was achieved more often if a post-thaw spindle was visualized. Of all slow-cooled and vitrified oocytes, a higher percentage of those slow-cooled achieved 2PN fertilization and usability. MS evaluation of oocytes cryopreserved by either method was associated with similar outcomes. CONCLUSION(S): OC outcomes are improving. An MS was almost always exhibited both before cryopreservation and after thawing, suggesting that, with appropriate technique, OC presents minimal harm to the MII oocyte. A meiotic spindle evaluation might help to further OC technology

OBJECTIVE: To determine whether there is a difference in pregnancy outcomes between women undergoing a shared versus exclusive donor oocyte cycle. DESIGN: Retrospective analysis. SETTING: University IVF center. PATIENT(S): Women undergoing either a shared (n=656 cycles), exclusive (n=225 cycles), or shared converted to exclusive (n=22 cycles) donor oocyte cycle from January 2000-December 2005. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Number of eggs retrieved, eggs fertilized, embryos transferred, embryos cryopreserved, clinical pregnancy rates (PR), live birth rates, spontaneous abortion rates. RESULT(S): Pregnancy outcomes in 656 shared cycles were compared with 225 exclusive cycles and 22 shared converted to exclusive donor oocyte cycles. Overall, there was no difference in the clinical PR among the three groups; however, the exclusive group did have a significantly greater number of embryos cryopreserved and this event occurred more frequently in such a cycle. CONCLUSION(S): Women undergoing a donor oocyte IVF cycle can choose to share the donor's oocytes with another recipient without compromising their PR; however, the probability of cryopreservation in such a shared donor oocyte cycle is significantly reduced. Therefore, the recipient must weigh the financial burden of an exclusive cycle with the desires for cryopreservation in an IVF cycle

Using a thyroid-stimulating hormone (TSH) cutoff of 2.5 mIU/L or 4.5 mIU/L, no differences in the rates of clinical pregnancy, delivery, or miscarriage were observed in this large, retrospective cohort study of first-cycle IVF patients from 2005 through 2008, after controlling for age. Although lowering the TSH threshold to 2.5 mIU/L would result in a nearly fivefold increase in the number of women being classified as hypothyroid, the lack of differences in maternal clinical outcomes must be considered in the current controversy regarding the relative merits of lowering the upper limit of normal of TSH