纵向剖开的子宫腔面可以看到明显增生的子宫内膜。子宫内膜腺体和间质细胞增多，导致子膜内膜增厚。这种增生是随月经周期而发生的生理性变化。
The prominent folds of endometrium in this uterus opened to reveal the endometrial cavity are an example of hyperplasia. Cells forming both the endometrial glands and the stroma have increased in number. As a result, the size of the endometrium has increased. This increase is physiologic with a normal menstrual cycle.