A prospective randomized comparative study between transdermal estradiol gel and oral estradiol valerate tablets for successful clinical outcome in frozen-thawed embryo transfer cycles

Abstract

Background: The aim of this study was to evaluate the use of transdermal estradiol gel and compare it with oral estradiol valerate tablets for the preparation of endometrium in frozen-thawed embryo transfer (FET) cycles. Methods: This prospective trial included 100 women undergoing FET cycles during study period and they were randomized into one of the two groups. Group 1 (n = 50) received oral estradiol valerate tablet and group 2 (n = 50) received transdermal estradiol gel from day 2 of menstrual cycle and endometrial thickness monitored with transvaginal ultrasonography. Primary outcome of this study was to compare clinical pregnancy rate (CPR) between the two groups. Secondary outcomes were implantation rates (IRs), CPRs, miscarriage rates (MRs), endometrial thickness at the start of progesterone, cycle cancellation rates, undesirable side effects, and patient satisfaction score. Statistical testing was performed with SPSS 17.0. Results: There was no clinically significant difference in biochemical pregnancy rate, CPR, IR, and MR between the two groups. Endometrial thickness on day of progesterone start was higher in group 2 as opposed to group 1 (9.81 ± 0.861 vs. 9.46 ± 0.830; P-value = 0.043) which was clinically significant. Almost 37.5% patients (n = 18) in group 1 had mild adverse effects when compared with only 12.76% (n=6) in gel group (group 2). Conclusion: We conclude that transdermal estradiol gel is equally efficacious as oral estrogen in hormone replacement FET cycles but with added advantage of better patient comfort and lesser side effects with transdermal gel.