[Comparison of clinical outcomes of four protocols for frozen-thawed embryo transfer cycle]

To compare the clinical outcome of 4 protocols of frozen-thawed embryo transfer cycle to select the optimal endometrial preparation method for frozen-thawed embryos transfer.A retrospective analysis of the 4 clinical protocols was conducted including natural cycle, down-regulated hormone replacement treatment (HRT) cycle, hMG cycle and natural cycle+hCG in endometrial preparation for 419 frozen-thawed embryos transfer cycle, and the clinical pregnancy rate, implantation rate, early abortion rate, ectopic pregnancy rate , ongoing pregnancy rate and delivery rate were compared between the 4 protocols.There was no significant difference between the 4 groups with different clinical protocols in age, duration of infertility, reason of infertility, number of embryo transferred and endometrial thickness. The 4 protocols differed little in the implantation rate, clinical pregnancy rate, biochemical pregnancy rate, early abortion rate, ectopic pregnancy rate, ongoing pregnancy rate and delivery rate in the four clinical protocols.The 4 clinical protocols for frozen-thawed embryos transfer all have favorable clinical outcome, and choice of a specific protocol should be made according to the a comprehensive consideration of the individual conditions of the patient.