Impact of insemination technique, semen quality and oocyte cryopreservation on pronuclear morphology of zygotes derived from sibling oocytes.

Pronuclear morphology seems to be an important predictive value of zygote development and integrity. In this study we want to evaluate the effect of insemination technique, male factor and oocyte cryopreservation on pronuclear morphology of zygotes derived from sibling oocytes in our Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Arcispedale S. Maria Nuova, Reggio Emilia, Italy. Subjects (n = 190) were submitted to IVF cycles with non-frozen and frozen sibling oocytes. Morphological evaluations were assessed using zygote pronuclear morphology (pronuclei, nucleoli and axis) in four groups: Group 1: 144 zygotes from 85 conventional IVF cycles with non-frozen oocytes; Group 2: 164 zygotes from 85 intracytoplasmic sperm injection (ICSI) cycles with Group 1 patients' sibling frozen oocytes; Group 3: 221 zygotes from 123 ICSI cycles with non-frozen oocytes; Group 4: 197 zygotes from 123 ICSI cycles with Group 3 patients' sibling frozen oocytes. No differences between Group 1 and Group 2 were seen. Group 3 was statistically different from Group 4 in relation to the nucleolar morphology. Oocyte cryopreservation procedure modified the nucleolar morphology of zygotes only in the presence of poor semen quality.

The effect of selecting oocytes for insemination and transferring all resultant embryos without selection on outcomes of assisted reproduction.

OBJECTIVE: To evaluate the effect of selecting three best oocytes for insemination and transfer of all resultant embryos on outcomes of assisted reproductive technologies (ART). STUDY DESIGN: Comparative study. SETTING: The Center of Reproductive Medicine, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy. PATIENT(S): Women undergoing ART during the period March 10, 2004 to March 9, 2006. INTERVENTION(S): Comparing outcomes of ART following transfers of 3 "excellent" (n = 267) embryos and cycles in which none of the embryos was considered "excellent quality" (n = 176). MAIN OUTCOME MEASURE(S): Rates of fertilization, pregnancy, "take-home baby," and multiple pregnancies. RESULTS: The average number of retrieved oocytes and the average number of inseminated oocytes of good quality were similar in both groups. Intracytoplasmic sperm injection was performed four to five times more often in cycles without "excellent quality" irrespective of the patient's age (odds ratio 4.6, 95% confidence interval 3.0, 7.1). The two groups had similar rates of implantation, total pregnancies/ET, clinical intrauterine pregnancy, singleton and multiple births, and "take-home" baby rate. This similarity persisted irrespective of the patient's age. CONCLUSION(S): The selection of oocytes for insemination and transfer of all available embryos irrespective of their quality did not change outcomes of ART.

Limited importance of pre-embryo pronuclear morphology (zygote score) in assisted reproduction outcome in the absence of embryo cryopreservation.

OBJECTIVE: To investigate the hypothesis that Z-score criteria represent a reliable predictor of implantation rate and pregnancy outcome in in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles, excluding the possibility of embryo selection before the embryo transfer. DESIGN: Retrospective clinical study. SETTING: Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Arcispedale S. Maria Nuova (ASMN), Reggio Emilia, Italy. PATIENT(S): We analyzed 393 pregnancies obtained by IVF or ICSI cycles. INTERVENTION(S): Morphologic evaluations of Z-score in pre-embryos obtained from IVF or ICSI cycles. MAIN OUTCOME MEASURE(S): Evaluations of Z-scores, implantation rate, and clinical pregnancy outcome. RESULT(S): We did not find any statistically significant correlation between the Z-score of 1032 embryos transferred in 393 embryo transfers and the implantation rate or the pregnancy outcome. In particular, the best Z-score identified (Z1, 7.2%) did not seem to correlate with embryo implantation rate or pregnancy outcomes any better than those with worse scores (Z2, 6.9% and Z3, 85.9%). CONCLUSION(S): Our results seem to confirm that Z-score alone cannot be considered a better tool than standard morphologic criteria for identifying, controlling, or selecting embryos with a better chance of successful ongoing pregnancy.