Primary amenorrhea in non-identical twins: An improbable cause

Background: Primary amenorrhea is often the first presenting symptom in mullerian agenesis. A thorough history and physical examination focusing on pubertal development assist in diagnosis and management. Mayer-Rokitansky-Kuster-Hauser syndrome (MRKH) is the second most common cause of primary amenorrhea with a reported incidence of 1:4000. Case: Non-identical 18-year-old twins presented with primary amenorrhea. They both had well developed secondary sexual characteristics, with no menarche. One of the twins complained of lower abdominal pain. They were initially assessed within a primary care setting. They were referred to a secondary care center for further investigations to reach a definite diagnosis and management. Further management was planned within a multidisciplinary approach involving gynecologists, psychologists and surgeons with a special interest in vaginal reconstructive surgery. Conclusion: Primary amenorrhea affects approximately 5% of amenorrheic women. Diagnosis and management are reached by following a diagnostic algorithm. Reports of MRKH in siblings or non-identical twins are rare. We believe this to be the first case of MRKH syndrome to be reported in dichorionic twins.