11. Accuracy of Imperforate Hymen Diagnosis at a Pediatric and Adolescent Gynecology Referral Center

Background Imperforate hymen (IH) is a congenital anomaly (CA) that results from unsuccessful canalization of the vaginal plate at the junction of the urogenital sinus (UGS) and uterovaginal canal and failed canalization of hymenal mucosa. IH is often discovered at puberty due to primary amenorrhea and cyclic pelvic pain secondary to vaginal outlet obstruction. The hymen and Müllerian system have different embryonic origins and it is important to distinguish congenital conditions based on their embryonic origins. Accurate diagnosis informs proper screening and management to minimize comorbidities. Given overlap in presentation among CA of the reproductive tract, our goal was to investigate the accuracy of IH diagnosis at a single referral center. Methods IRB approval was obtained for this study. A retrospective chart review identified 179 patients based on ICD-10 codes for hymenal abnormality who were seen at our center from January 1, 2017 – February 28, 2023. Data collection included demographics, presentation, diagnosis from referring provider, diagnostic work-up, diagnosis once referred to pediatric gynecology, management, and final diagnosis. Descriptive statistics were utilized. Results 165 patients met inclusion criteria for hymenal abnormality. Mean age at presentation was 9.3 years (standard deviation (SD) = 5.7). The cohort was ethnically diverse. 57 were initially diagnosed with IH by primary care providers referring patients to a pediatric gynecology clinic. Of those patients, 28 (49.1%) were misdiagnosed. Common conditions misdiagnosed as IH: vaginal atresia (9/28, 32.1%), microperforate hymen (4/28, 14.3%), Müllerian anomalies (3/28, 10.7%), and normal external genital exam without IH in 4 patients (14.3%). Additionally, 5 patients were misdiagnosed with various vulvovaginal conditions instead of IH. Workup varied among referring providers but was primarily achieved by referral to pediatric gynecology and a combination of physical exam and imaging findings. Conclusions IH has an incidence of 0.05-0.1%. As a result, many providers are not familiar with the diagnosis and will not see the condition during their practice. IH is important to distinguish from other anomalies of the reproductive tract, as the surgical management is different depending on the CA. Therefore, misdiagnosis of IH may lead to an incorrect surgical approach and subsequent complications. Misdiagnosis as another condition rather than IH, may also lead to delays in surgical management without early referral for other reproductive tract CA. Training and education surrounding IH, along with referral to pediatric gynecology, may help reduce misdiagnosis.