Investigators aim to collect endometrial sampling with Li Brush among target population who have risks for endometrial neoplasm, then Fractional curettage should performed with these participants, investigators intend to compare the pathological diagnosis results of cytology and fractional curettage to evaluate the sensitivity of Li Brush and investigators expect that the brush can be used for screening of endometrial cancer in the postmenopausal period in the clinic.

Investigators screen the suitable participants according to the inclusion and exclusion standards, and then collect their endometrial sampling with Li Brush. Pathologists will help to decide the cytology obtained by Li Brush and histology diagnosis of the endometrial sampling. Comparing the pathological diagnosis results of cytology and histology, investigators want to prove the feasibility of cytology diagnosis of endometrial cancer in the postmenopausal period, as the same time, investigators intend to evaluate the possible factors that affecting the precision of Li Brush for endometrial cancer in the postmenopausal period.

Inclusion Criteria:

1. Postmenopausal abnormal uterine bleeding;
2. Ultrasound of the pelvic showed thickened endometrial ( usually more than 5mm) ;
3. Family history of endometrial cancers;
4. Other participants with risks for endometrial cancer (such as fat, Lynch Syndrome and so on)

Exclusion Criteria:

1. Cervical cancer;
2. Fever (body's temperature is higher than 37.5 degrees );
3. Vaginitis (excluding atrophic vaginitis);
4. Patients who cannot bear the operation;
5. Coagulation disorders;
6. Pregnancy and suspected pregnancy.

participants with risks of endometrial cancer in the postmenopausal period