A Research On Correlation Between Frozen-thawed Embryo Transfer And Embryo Implantation

Objective: Close attention is being paid to frozen-thawed embryo transfer gradually as an effectively supplementary treatment for assisted reproductive technology (ART). Referring to the endometrial preparation programs for frozen-thawed embryo transfer, there were two main choices in clinic: natural cycle and hormone-replacement cycle. With regard to their effects on clinical pregnancy rate, there are different points of view. Therefore, the aim of this study was to determine whether their effects on clinical pregnancy rate are different, which might guide to choose the better endometrial preparation program for frozen-thawed embryo transfer in clinic. Because a large number of frozen-thawed embryo transfer pregnancies failed during the implantation stage, the receptivity of endometrium to the embryo becomes an investigative hot spot now. Endometrial biopsy and uterine lavage technique, which have been used for studies of endometrial receptivity are invasive and might negatively affect an ongoing pregnancy. For those reasons, they couldn't be used in frozen-thawed embryo transfer treatment cycle. Several lines of evidence indicated that cytokines and growth factors might play a role in embryo implantation, such as leukemia inhibitory factor (LIF),...