Those who didn't conceive on the sixth cycle (41 women) were asked to have an extra (7th) cycle in which they were prescribed the usual dose of Clomiphene citrate in addition to sildenafil vaginal gel. The sildenafil vaginal gel consists of sildenafil acetate as a medicament loaded on an in situ gelling system based on two polymers: Pluronic p-127, and Hydroxy Ethyl Cellulose. The dose was 5 g gel containing 50 mg sildenafil, applied vaginally twice daily from cycle day 8 to Day of HCG injection. The gel was prepared in collaboration with the department of pharmaceutics, faculty of Pharmacy, Assiut University. Sixty grams of gel were prepared in tubes and every patient was given 10 applicators like that used for administration of vaginal antimycotic creams to use them for applying the gel.