Background <p>Adenomyosis is a benign condition of the uterus. There are few studies available on the prevalence of adenomyosis among women experiencing infertility. This study was designed to use ultrasound imaging to determine the frequency of adenomyosis in infertile women.</p> Methods <p><?tk 4?>This prospective cross-sectional screening study included 963 eligible infertile women referring to the infertility clinic of Royan Institute for the first time between 2017 and 2020. The women were referred for a transvaginal ultrasound before initiating the treatment. Exclusion criteria involved women: aged &gt;45 years, with multiple and large fibroids, who had vaginismus, and those who did not feel inclined to participate in the study. Participants were divided into groups of women with adenomyosis and without adenomyosis.</p> Results <p><?tk 4?>The overall prevalence of adenomyosis was found to be 17.13%, of which 53.42% were severe adenomyosis. The mean age was significantly higher in the adenomyosis group than in the non-adenomyosis group (32.06 ± 5.31 vs. 29.51 ± 5.27 years, <i>P &lt; </i>0.001). The prevalence of women with adenomyosis who had concomitant fibroids and ovarian endometrioma was 21.81% and 8.48%, respectively. The results of the multivariate logistic regression analysis showed that age, type of infertility, presence of ovarian endometrioma and fibroids, and causes of infertility were significantly associated with adenomyosis.</p> Conclusion <p><?tk 4?>Adenomyosis seems to be a clinical condition with a high prevalence in infertile women, indicating the importance of routine myometrial evaluation during infertility assessment to enhance patient counseling and management.</p>