If it's more than 4 millimetres thick, then a biopsy or a dilation and curettage procedure is used to remove some endometrial cells and confirm the diagnosis.

如果子宫内膜厚度超过4毫米，就需要进行活检或宫颈扩张及刮宫术，来获取子宫内膜细胞以确诊。