Comparison of Endometrial Thickness with Concomitant Administration of Sildenafil Citrate and Ethinyl Estradiol vs Ethinyl Estradiol Alone for Frozen Embryo Transfer

Introduction: Infertility is one of the common medical issues in today's world. One of the common causes of infertility is the lack of implantation of the embryo. Aim: To compare the effect of Ethinyl Estradiol (E2) alone on Endometrial Thickness (ET) with that of sildenafil citrate and E2 combination. Materials and Methods: In this clinical trial, 70 infertile women undergoing treatment with Assisted Reproductive Techniques (ARTs) were randomly divided into two groups of 35 each. One group received E2 and vaginal sildenafil and the other E2 alone. On the seventh day of the cycle and, if necessary, until ET reached 8 mm, ET in both groups was measured by transvaginal ultrasound. After the embryo transfer, Beta-Human Chorionic Gonadotropin (BHCG) was performed in both groups. The measured thickness of uterus and BHCG were recorded in the checklist for both groups. Data were analysed by SPSS and p<0.05 was considered significant. Results: The mean duration (in days) to reach an 8 mm ET in infertile women in the E2+sildenafil group (13.59 +/- 3.07) was lower than that in the E2 group (14.88 +/- 4.78), yet insignificant (p=0.21). Although the mean dose (mg) of E2 and duration (day) to reach an 8 mm ET in the E2+ sildenafil group was lower than those in the E2 group, significance (p) levels were 0.02 and 0.21, respectively. Conclusion: In infertile women undergoing ARTs, co-administration of sildenafil citrate and E2 increased ET relatively and reduced the dose of E2 and the duration of its administration.