Urogenital Hiatus

The urogenital hiatus is an opening in the anterior part of the pelvic floor through which the urethra and, in females, the vagina pass. It lies within the levator ani region and is bounded and supported by an interconnected complex that includes levator muscles, the perineal membrane, perineal body, and vaginal connective tissues .¹

The hiatus is not a rigid hole. Its dimensions and shape change with muscle contraction, relaxation, body position, increases in abdominal pressure, and childbirth-related changes. Pelvic-floor contraction helps narrow and close the region, while relaxation permits functions such as urination and vaginal passage. Imaging studies can measure hiatal dimensions, but values depend on the anatomical landmarks and testing condition .¹

The urogenital hiatus is related to, but not always identical with, the broader term levator hiatus used in pelvic-floor imaging and anatomy. Enlargement of the hiatal region is associated with pelvic-organ support disorders, but the size of the opening alone does not define pelvic-floor function. The concept is best understood as a dynamic anatomical passage whose closure depends on coordinated muscle and connective-tissue relationships .¹