Effect of vaginal estrogen cream on endometrial thickness in women under embryo transfer by applying long protocol method

Background and aims: Endometrial thickness (ET) is one of the main parameters in the success of assisted reproductive technology (ART) methods, which is influenced by sex steroids. This study investigated the effect of vaginal estrogen cream on ET in women undergoing embryo transfer. Methods: In this clinical trial, 100 infertile women candidates for embryo-fetal transfusion were enrolled in the study by a simple sampling method and then randomly divided into two treatment groups. For patients in group A, estradiol tablets were administered alone (control) and group B received the estradiol plus vaginal estrogen cream (intervention). The thickness of the endometrium was measured by ultrasound in both groups and recorded in the checklist. The rate of positive bHCG, pregnancy, and canceled cycles was evaluated in both groups as well. Finally, the data were analyzed using SPSS software. Results: Both groups were matched in terms of age (P=0.129). There was no significant difference between the groups regarding ET (P=0.651) and bHCG frequency (P=0.418) and the pregnancy rate was similar in two groups. Based on the results, the frequency of the canceled cycles was 32% and 50% in intervention and control groups (P=0.031).Eventually, no significant relationship was observed between pregnancy outcome (0.637) and the bHCG (0.553) test with ET. Conclusion: Overall, the administration of vaginal estrogen cream has no effect on ET and pregnancy rate in women under embryo transfer by applying the long protocol method in patients who referred to endometrium and endometriosis research center but it significantly reduces the eliminated cycles