In this prospective randomized trial, the parameters of the frozen-thawed embryo transfer
(FET) cycles were analyzed. This study was undertaken in the Department of Assisted
Reproductive Technologies and Reproductive Genetics Center at Istanbul Memorial Hospital with
approval of the local ethics committee. The aim of this prospective randomized clinical trial
was to compare two methods of endometrial preparation for FET, oral estradiol and estradiol
transdermal patch.