Can we improve implantation by cancellation of fresh embryo transfer?

Abstract

Single embryo transfer is becoming increasingly popular in IVF/ICSI. More IVF/ICSI cycles therefore include freezing of high quality embryos, and the cumulative effect of such cycles becomes more important. To improve the results obtained using frozen–thawed embryos, the predictive value of embryo and patient characteristics such as ovarian reserve, hormone levels and age play an important role in both cases whether the women treated with oestradiol/progesterone or undergo natural cycle transfer. Although, embryo quality indicators revealed sometime morphologically and numerically inferior embryo cohorts after cryopreservation, the clinical pregnancy rate is higher in cycles using thawed embryos compared with fresh. Moreover, subsequent logistic regression analysis controlled for differences in embryo quality and revealed significantly greater probability of clinical pregnancy with thawed embryos when compared with fresh, suggesting a negative effect of ovarian stimulation on endometrial receptivity. The aim of this study is to discuss an idea of cancellation of a fresh embryo transfer and put on an alternative method which is the frozen thawed embryo.

Keywords

• Frozen–thawed embryo
• Vitrification
• Cryopreservation
• Embryo selection