Dawood, S. A. ., Jwad, M. A. ., & Hussaini, H. A. (2020). A Comparison Between the Effect of Vaginal Sildenafil Versus Oral Estradiol Valerate on Ultrasound Parameters of Endometrial Receptivity and Follicular Growth in Iraqi Females Receiving Letrozole for Induction of Ovulation. Iraqi Journal of Embryos and Infertility Researches, 10(1), 35–50. https://doi.org/10.28969/IJEIR.v10.i1.r3