Diagnostic Ultrasound - Abdomen and Pelvis

Uterus
CYCLIC CHANGES OF ENDOMETRIUM
Anatomy: Pelvis
Endometrium, early secretory phase
Endometrium, secretory phase
Shedding endometrium, onset of
menstruation
Trace fluid in canal
(Top) Longitudinal TV scan shows the endometrium during the early secretory phase. The endometrium becomes progressively
thickened and more echogenic, with loss of the trilaminar appearance. These are cyclic endometrial changes in a neutral uterus.
(Middle) Longitudinal TV ultrasound in the late secretory phase shows the endometrium is uniformly thickened and echogenic. The
normal maximal endometrial thickness should not exceed 1.6 cm. Through transmission can sometimes be visualized secondary to the
mucus-filled glands. (Bottom) Longitudinal TV ultrasound shows a thickened endometrium just prior to menstruation. Echogenicity has
decreased and is more heterogeneous than in the secretory phase. A small amount of fluid can be seen within the endometrial cavity.
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