Uroplakins play conserved roles in egg fertilization and acquired additional urothelial functions during mammalian divergence.

Uroplakin (UP) tetraspanins and their associated proteins are major mammalian urothelial differentiation products that form unique two-dimensional crystals of 16-nm particles ("urothelial plaques") covering the apical urothelial surface. Although uroplakins are highly expressed only in mammalian urothelium and are often referred to as being urothelium specific, they are also expressed in several mouse nonurothelial cell types in stomach, kidney, prostate, epididymis, testis/sperms, and ovary/oocytes. In oocytes, uroplakins colocalize with CD9 on cell-surface and multivesicular body-derived exosomes, and the cytoplasmic tail of UPIIIa undergoes a conserved fertilization-dependent, Fyn-mediated tyrosine phosphorylation that also occurs in Xenopus laevis eggs. Uroplakin knockout and antibody blocking reduce mouse eggs' fertilization rate in in vitro fertilization assays, and UPII/IIIa double-knockout mice have a smaller litter size. Phylogenetic analyses showed that uroplakin sequences underwent significant mammal-specific changes. These results suggest that, by mediating signal transduction and modulating membrane stability that do not require two-dimensional-crystal formation, uroplakins can perform conserved and more ancestral fertilization functions in mouse and frog eggs. Uroplakins acquired the ability to form two-dimensional-crystalline plaques during mammalian divergence, enabling them to perform additional functions, including umbrella cell enlargement and the formation of permeability and mechanical barriers, to protect/modify the apical surface of the modern-day mammalian urothelium.

Fate of cryopreserved donor embryos.

OBJECTIVE: To review a center's experience with cryopreserved embryos generated from donor eggs and to analyze their long-term disposition. DESIGN: Retrospective analysis of donor egg cycles with cryopreserved embryos. SETTING: University-based IVF program. PATIENT(S): Eight hundred twenty-nine women undergoing oocyte donation. INTERVENTION(S): N/A. MAIN OUTCOME MEASURE(S): Factors affecting the decision regarding disposition of donor frozen embryo transfer (dFET) and the association between fresh and dFET cycles. RESULT(S): From January 2000 to December 2004, donor egg recipients underwent 829 fresh embryo transfer cycles that resulted in a 54% live birth rate. Of the 444 recipients who delivered, 177 (40%) also cryopreserved embryos at transfer; however, only 37 (21%) returned for a dFET by August 2009 and only 18 women had children from fresh and frozen transfers. In contrast, 128 of the 385 recipients who failed the fresh transfer (33%) cryopreserved embryos and 111 (87%) returned for a dFET. Of these, 44 had children from the dFET. Frozen cycle success rates between these recipient groups did not depend on fresh cycle outcome or prior parity. CONCLUSION(S): Donor oocyte recipients often initiate treatment with a desire to cryopreserve embryos for future use and family expansion. However, our data demonstrates that most recipients with a child from the fresh transfer do not return to use their cryopreserved embryos. Although fresh transfer success correlated with embryo disposition, it did not correlate with the outcome of thawed embryo transfer.

Comparison of pregnancy outcomes in anonymous shared versus exclusive donor oocyte in vitro fertilization cycles.

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.

Comparison of pregnancy outcomes in elective single blastocyst transfer versus double blastocyst transfer stratified by age.

OBJECTIVE: To determine whether there is a difference in pregnancy outcomes, stratified by age, between women undergoing elective single blastocyst transfer (eSBT) versus those undergoing double blastocyst transfer (2BT). DESIGN: Retrospective analysis. SETTING: University IVF center. PATIENT(S): A total of 1,141 nondonor IVF cycles in women aged <40 years from January 2004-March 2007. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Eggs retrieved, embryos cryopreserved, implantation rates, clinical pregnancy rates (PR), live birth rates (LBR), spontaneous abortion rates (SAB). RESULT(S): Pregnancy outcomes in 52 cycles of women <40 years of age who underwent eSBT were compared with 1,086 cycles of women who underwent 2BT in fresh IVF cycles from January 2004-March 2007. Overall, the eSBT was associated with a statistically significant 92% reduction in the twinning rate (from 25%-2%) while maintaining a high clinical PR (63% in the eSBT group vs. 61% in the 2BT group). CONCLUSION(S): Women who are <40 years of age undergoing nondonor fresh IVF cycles can electively choose to transfer a single blastocyst for the purpose of significantly reducing their risk of multiples without compromising their PR.

Women with cancer undergoing ART for fertility preservation: a cohort study of their response to exogenous gonadotropins.

Cancer patients produce similar numbers of oocytes after ovarian hyperstimulation compared with age-matched infertile controls, suggesting that malignancy does not adversely affect ovarian response.

Heterotopic abdominal pregnancy following two-blastocyst embryo transfer.

OBJECTIVE: To report a case of a heterotopic primary abdominal pregnancy after two-blastocyst IVF-ET. DESIGN: Case report. SETTING: University-based IVF program. PATIENT(S): A woman with a heterotopic abdominal pregnancy after IVF-ET. INTERVENTION(S): Pituitary down-regulation with luteal antagon, ovulation induction with menotropins, IVF-ET, progesterone in oil for luteal support, dilation and curettage for missed abortion, laparoscopy, and resection of abdominal gestation. MAIN OUTCOME MEASURE(S): Human chorionic gonadotropin levels, pelvic ultrasound examinations, and laparoscopic and pathologic findings. RESULT(S): A heterotopic abdominal pregnancy occurred after a two-blastocyst IVF-ET. The concurrent intrauterine gestation resulted in a miscarriage. CONCLUSION(S): The number of embryos transferred has been identified as a powerful risk factor for heterotopic pregnancy; however, heterotopic pregnancy can occur following a two-embryo, blastocyst stage transfer.