Uterus, Sagittal View

Description

Uterus in midline sagittal section reveals the layered uterine wall and the continuous lumen from fundus to cervix. Superiorly, the domed fundus transitions into the uterine body, where the endometrium lines the uterine cavity and is surrounded by the thicker myometrium; the serosal contour (perimetrium) forms the outermost surface along the anterior and posterior walls. Inferiorly, the cavity narrows into the isthmus and cervical canal, with the endocervical mucosa forming a distinct channel that opens toward the vagina at the external os. Orientation is strict anteroposterior, so the relationship of the anterior uterine wall to the cervix and lower uterine segment reads in one plane. Endometrial thickness and contour in this sagittal cut matter for both physiology and pathology, since proliferative and secretory phases change the echogenic counterpart of this lining and guide interpretation of abnormal uterine bleeding. A focal distortion of the uterine cavity suggests submucosal leiomyoma or an endometrial polyp, while diffuse thickening of the myometrium adjacent to the endometrium supports teaching points around adenomyosis and the junctional zone. Cervical canal caliber and angulation provide a practical anatomic basis for why instrumentation can meet resistance at the internal os, and why uterine sound depth and direction should follow the uterine axis during intrauterine device placement. Small space, big consequences. You can place this illustration into gross anatomy, embryology of Müllerian derivatives, or OB-GYN teaching modules that compare normal uterine architecture with hysteroscopic findings, endometrial biopsy targets, and common sites of postpartum hemorrhage interventions at the level of the lower uterine segment. It also suits patient-facing diagrams for hysterectomy counseling, where preserving the distinction between uterine cavity, cervix, and cervical canal prevents misunderstandings. Anatomical accuracy verified by SciePro's Medical Advisory Board.