To describe the incidence and management of vaginal stricture after uterus transplantation (UTx) in the US, to propose a grading system to classify stricture severity, and to identify risk factors for stricture formation. Prospective cohort study. University Hospital. Recipients undergoing UTx from 2016-2023 at Baylor University Medical Center in Dallas, Cleveland Clinic, the University of Pennsylvania, and the University of Alabama at Birmingham were monitored postoperatively with regular pelvic examinations. Stricture was defined as vaginal narrowing of <3 cm in patients with graft survival of at least 7 days. Demographic and surgery characteristics. Stricture development and severity (grade 1 for diameter 2-<3 cm, grade 2 for 1-<2 cm, or grade 3 for <1 cm). Of the 45 UTx from 2016-2023 (16 deceased donors and 29 living donors), 3 were excluded from the analysis because of graft loss within 7 days. Of the 42 remaining recipients, 39 (92.9%) had Mayer-Rokitansky-Küster-Hauser syndrome and 3 (7.1%) had a prior hysterectomy. Twenty-eight (66.7%) UTx recipients developed postoperative vaginal strictures with a median time to stricture of 33 days (interquartile range 19-53 days). Most strictures were of moderate severity, with 4 (14.3%) strictures categorized as grade 1, 19 (67.9%) as grade 2, and 5 (17.9%) as grade 3. History of Mayer-Rokitansky-Küster-Hauser syndrome and preoperative recipient vaginal length were significant risk factors for stricture, after adjustment for donor and recipient age and body mass index, anastomosis technique, total ischemia time, center, and year. Patients with longer preoperative vaginal length had a lower risk of stricture (hazard ratio 0.45, 0.29-0.70). The severity grading of the stricture was associated with the effectiveness of a nonoperative treatment approach (grade 1 vs. grade 3). No patients with grade 3 strictures improved with self-dilation alone; all required surgical repair and/or dilation under anesthesia. Conversely, for grade 1 or 2 strictures, self-dilation alone was successful in 47.8% (11/23), and no grade 1 strictures required surgical repair. Vaginal stricture is a common postoperative complication after UTx, affecting >65% of recipients. Short preoperative vaginal length and history of müllerian agenesis in the recipient are significant risk factors. Vaginal self-dilation was effective for some mild to moderate strictures, although dilation under anesthesia or surgical repair was required in most cases. Dallas UtErus Transplant Study (DUETS) at Baylor University Medical Center (NCT02656550), Uterine transplantation for the treatment of uterine factor infertility at the Cleveland Clinic (NCT02573415), The University of Pennsylvania Uterus Transplant for Uterine Factor Infertility Trial (UNTIL) (NCT03307356).