Factors Influencing Pregnancy Outcome Following Slow Cooling Cryoembryo Transfer and Risk of Multiple Conception

Objective To investigate the factors that influence the potential for cryoembryo implantation and multiple pregnancy. Methods In this retrospective study, a total of 93 7 thawing cycles （859 couples） in which 3286 d 3-embryos were thawed. Rates of implantation, clinical pregnancy and multiple conception following FET were observed. Results There were significant differences in female age （P〈0.05） and number of good quality embryos （P〈0. 05） between cycles that resulted in pregnancy and those did not. There was a trend toward decreasing rates of implantation, clinical pregnancy and multiple pregnancy with increasing female age. Compared with transferring 1 good quality embryo, clinical pregnancy rate of transferring 2 and 3 good quality embryos was increased significantly （P〈0. 001）, there was no significant difference in clinical pregnancy rate between transferring 2 and 3 good quality embryos. Multiple pregnancy rate was increased significantly in the group of transferring 3 good quality embryos （P〈0.05）,but there was no significant differences in multiple pregnancy rate between transferring 1 and 2 good quality embryos. Younger women （≤ 30 years） also had a significantly higher multiple pregnancy rates （28.13%） than the older ones（〉35 years） （13.64%）. With an increase in age from ≤ 30 years to〉40 years, clinical pregnancy rate declined from 47 61% to 25.00%.Conclusion Female age and the number of gooa quality embryos transferred are important factors influencing the clinical and multiple pregnancy rate, reducing the number of good quality embryos transferred may decrease the rate of multiple pregnancy but do not affect the clinical pregnancy rate.

Comparison of Effects of Recombinant FSH versus Highly Purified Urinary FSH for COH in the Outcome of IVF-ET

Objective To investigate the difference in the outcome of IVF-ET between the patients using recombinant FSH versus highly purified urinary FSH for controlled ovarian stimulation （COH）. Methods A comparative retrospective analysis was performed between the patients undergoing IVF using recombinant FSH （rFSH） 562 cycles （rFSH group） versus using highly purified urinary FSH（uFSH） 555 cycles （uFSH group） for COH from August 2009 to July 2010. Main outcome measures included： duration of stimulation, total amount of FSH, E2 level on hCG injection day, number of oocytes collected, average number of frozen embryos, and the rate of cancellation, implantation, clinical pregnancy and miscarriage rate. Results uFSH group required a significantly higher total amount of FSH and a longer duration of stimulation than thouse rFSH group （19.3 ± 7.6 vs 18.3 ± 7.0 ampoules, P=0.02, and 9.1 ± 1.6 d vs 8.9 ± 1.5 d, P=0.04, respectively）. There was no statistically significant difference in the implantation rate, clinical pregnancy rate and miscarriage rate between uFSH and rFSH groups （22.57% vs 20.16%, 38.15% vs 35.18%, and 10.6% vs 13.45%, respectively, P〉0.05）. The other measures including E2 level on hCG injection day, cancellation, number of oocytes collected, fertilization, average number of frozen embryos showed no difference between the two groups. Conclusion There is no significant difference in the outcome of IVF-ET between two groups in effects of recombinant FSH versus highly purified urinary FSH for COH.