OBJECTIVE: Vaginal dilation treatment has been shown to be a (cost) effective first-line alternative to surgery in normalizing vaginal length and improving sexual function in women with vaginal hypoplasia. There remains, however, a need for prospective studies, with long-term assessment of multiple outcomes. STUDY DESIGN: This was a prospective, single-centre observational study of 16 women with Mayer-Rokitansky-Kuster-Hauser syndrome (n = 12) or 46,XY disorders of sex development (n = 4). All women underwent an outpatient vaginal dilation program supervised by a psychologist and physiotherapist. At baseline (TO), stop of treatment (T1) and 1 year follow-up (T2), semistructured interviews, and validated questionnaires assessed sexual functi...