Normal Uterus. A. Transabdominal sagittal plane image through the urine-filled bladder (B) demonstrates the smooth contour and pear shape of the normal uterus (U). The endometrium (betweenarrowheads) is more echogenic than the surrounding myometrium. This image demonstrates the typical three-layer appearance of proliferative phase endometrium. The cervix (C) protrudes into the upper vagina (V) at the intersection between the long axis of the uterus and the axis of the vagina. B. Transvaginal sagittal-plane image of the uterus demonstrates the improved resolution of this technique. The endometrium (between arrowheads) is more sharply defined and the myometrium is more clearly evaluated. This image demonstrates the typical uniformly echogenic appearance of secretory phase endometrium.

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