Background: To determine the value of the uterocervical angle for predicting the displacement of copper intrauterine devices (IUDs). Methods: We conducted a prospective cohort study between December 2020–June 2021 at the family planning outpatient clinics of the Kanuni Sultan Suleyman Training and Research Hospital, Istanbul Health Sciences University. A total of 143 patients who had copper IUDs (T-Cu380A) inserted for contraception were evaluated from the 6th week to 5 years after insertion. Patients were divided into two groups according to ultrasonographic examinations that revealed whether their IUD were “displaced” or in the “normal” position. The uterocervical angle (UCA) of patients was measured by transvaginal ultrasonography and investigated as to whether it was predictive for the displacement of copper IUDs. Results: Of the 143 women participating in the study, 67 (46.9%) had a displaced IUD position, and 76 (53.1%) had a normal IUD position. No statistically significant difference was found between the two groups for patient age, body mass index, educational status, gravida, parity, and mode of delivery (p > 0.05). The mean anterior UCA of patients with displaced IUDs was 139.7 \pm 8.2 degrees, while the mean UCA of patients with normal IUD positions was 125.3 \pm 12.9 degrees. Multiple logistic regression analysis revealed that IUD displacement increased 1.31-fold with each one degree increase in the UCA (95% confidence interval (CI): 1.06–1.63, p = 0.012). Conclusions: The anterior UCA has predictive value for the displacement of copper IUDs. Measurement of the anterior UCA is a feasible method for predicting copper IUD displacement and can thus be used as a screening tool to allow additional counseling for patients. The cut-off predictive value for the UCA was measured as 139.5 degrees. Women with a UCA >139.5 degrees may benefit from additional counseling and closer follow-up after device placement.