Introduction

Herlyn-Werner-Wunderlich syndrome (HWWS), also known as obstructed hemivagina with ipsilateral renal agenesis (OHVIRA), is a rare congenital anomaly involving both Müllerian and Wolffian duct development. It is classically characterized by the triad of uterus didelphys, obstructed hemivagina, and ipsilateral renal agenesis [1,2]. Müllerian duct anomalies are relatively uncommon, with a reported prevalence of 0.8%-4% in the general population, while OHVIRA syndrome represents a particularly rare subset, with an estimated incidence of approximately 1 in 20,000 [3].

Clinically, the syndrome typically manifests after menarche, most commonly as progressive dysmenorrhea. However, the diagnosis is frequently delayed due to its nonspecific presentation and the presence of a patent contralateral hemivagina, which may give the impression of normal menstruation. Such delays can result in complications related to chronic outflow obstruction, including hematometra, pelvic infection, and long-term sequelae such as endometriosis, pelvic adhesions, and infertility [4,5].

In this report, we describe a 16-year-old adolescent presenting with progressive dysmenorrhea in whom delayed diagnosis led to the development of pelvic endometriosis. Initial evaluation with ultrasonography suggested a Müllerian duct anomaly and adnexal pathology, while magnetic resonance imaging (MRI) provided definitive characterization, confirming HWWS with associated hematometra and ovarian endometrioma. This case highlights the pivotal role of radiologic imaging, particularly MRI for accurate diagnosis and evaluation of associated complications in HWWS.