The Vulvar Vestibule, a Small Tissue with a Central Position: Anatomy, Embryology, Pain Mechanisms, and Hormonal Associations

Abstract: The vulvar vestibule is the tissue located between the vagina and the vulva, comprising the vaginal introitus. It is mainly considered in the context of localized provoked vestibulodynia, a pain condition causing dyspareunia in 8–16% of women. Purpose of Review: To describe the vulvar vestibule’s unique properties, which may have a role in the development of vestibular tenderness and dyspareunia. Recent Findings: The vestibule displays different neural features when compared with neighboring organs. It is an immunologically diverse tissue that exhibits highly localized and tissue-specific pro-inflammatory responses. Systemic, as well as local hormonal-associated processes regarding estrogen, androgens, and usage of hormonal contraception apear to influence the pain threshold in the vestibule. Summary: The vestibule, emerging from the embryonic endoderm, exhibits unique features regarding innervation, inflammation, and hormonal stimuli. A better understanding of these mechanisms is required in order to advance our understanding of introital dyspareunia.