To study and compare the effect of vaginal sildenafil and estradiol valerate on endometrial thickness, blood flow and pregnancy rates in infertile women undergoing intrauterine insemination

Suchika Mangal, Shuchita Mehirishi


Background: The objective of this study was to study and compare the effect of vaginal sildenafil citrate and estradiol valerate on endometrial thickness, blood flow and pregnancy rates in infertile women undergoing intrauterine insemination (IUI).

Methods: It is a comparative prospective study including 100 women with primary or secondary infertility with stimulated cycles undergoing IUI. Patients with thin endometrium were randomly distributed in two groups. In group A, 50 patients were included and given sildenafil citrate 25 mg vaginally every 6 hours from day 8th of the cycle. In group B, 50 patients were given tablet estradiol valerate 2 mg 6-8 hourly. Patients were evaluated by trans-vaginal sonography (TVS) on day 13th of cycle for endometrial thickness and pattern with number and size of Graffian follicle.

Results: Mean endometrial thickness at the time of hCG trigger was 9.42 mm in sildenafil group and 9.94 mm in estradiol group (p value 0.14). 64% patients given sildenafil vaginally had vascularity up to zone 3 whereas 48% patients given estradiol valerate orally had zone 3 endometrial vascularity (p value = 0.038). The clinical pregnancy rates were 10 (20%) in group 1 and 7 (14%) in group 2 after 3 cycles of IUI. (p value = 0.042).

Conclusions: Both estradiol valerate and Sildenafil citrate can be used for improving the endometrium. Sildenafil when compared to estradiol valerate has better results as far as endometrial vascularity is concerned and marginally increased pregnancy outcome in patients undergoing IUI.


Infertility, Sildenafil, Estradiol valerate, Endometrial thickness

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