The return of menstruation in women after menopause is medically known as postmenopausal vaginal bleeding. Postmenopausal vaginal bleeding is one of the common symptoms in middle-aged and elderly women. There are many reasons for postmenopausal vaginal bleeding, as some postmenopausal vaginal bleeding may be due to gynecologic malignancies, so we should not be careless and should seek timely medical attention to identify the cause and provide targeted treatment. If you have vaginal bleeding after menopause, first of all, endometrial cancer, cervical cancer and other malignant tumors of the reproductive tract should be excluded, but it can also be caused by senile vaginitis, cervical polyps and endometritis. 1.Endometrial cancer mostly occurs in older women, with the prevalence age ranging from 50 to 69 years old, and postmenopausal women accounting for 70% to 75%. Those who have the following medical history should pay high attention: long-term anovulatory dysfunctional uterine bleeding, late menopause, no childbirth or few deliveries; long-term estrogen replacement therapy or long-term tamoxifen use; endometrial hyperplasia; obesity, diabetes and hypertension triad; family history of endometrial cancer, ovarian cancer and breast cancer. Early stage patients may be asymptomatic and typically present with irregular vaginal bleeding, abnormal vaginal discharge, abdominal pain, and fluid or pus accumulation in the uterine cavity. In post-menopausal women, the symptoms are mostly a small amount of bloody vaginal discharge after menopause, either continuously or intermittently, or occasionally a large amount of vaginal bleeding suddenly appears several years after menopause. Commonly used tests include: cytology, which occasionally reveals abnormal glandular cells and has screening value. Ultrasonography may show no significant changes in the early stages, but the lesion progresses with thickened and irregular endometrium, internal echogenic heterogeneity, and enlarged uterine cavity. In the late stage, the uterus is enlarged and the endometrial line is not clear. Involvement of the myometrium is seen as a thinning and deformation of the myometrium. Pathological histological examination is the basis for confirming the diagnosis of endometrial cancer. It can also clarify the tissue type, cell differentiation degree and other prognostic factors. Commonly used methods include diagnostic curettage, segmental scraping and endometrial biopsy, among which segmental scraping is the most common. If endometrial cancer is highly suspected, hysteroscopy, CT and MRI can be performed. Other indicators such as serum CA125 may also be elevated. 2.Cervical cancer Cervical cancer (also known as cervical cancer) is one of the major malignant tumors endangering women’s health worldwide and the most common malignant tumor of the reproductive system in Chinese women. Among Chinese women, cervical cancer is more common in middle-aged women. Most of the early stage cervical cancer has no special symptoms and signs. Some patients have increased leucorrhea, contact bleeding or irregular vaginal bleeding. Some cervical cancers occur after menopause and will show symptoms of postmenopausal vaginal bleeding and increased vaginal discharge. 3. Age-related vaginitis is mainly caused by lowered estrogen levels and is most common in post-menopausal women. As estrogen levels decrease, the vaginal wall atrophies and the mucous membrane thins, local resistance decreases and pathogenic bacteria invade and multiply, causing inflammation. The inflammation is often characterized by increased vaginal discharge, which may be purulent and bloody in severe cases. Itching and burning of the vulva and painful urination can be observed. Gynecological examination shows atrophy of the vaginal mucosa, loss of folds, congestion, spotting and bleeding of the mucosa, and in severe cases, ulcers may form. If the ulcer is not treated early, scar contracture may occur and lead to vaginal stenosis, and poor drainage of secretions may lead to pus accumulation in the uterine cavity or vagina. Other gynecological diseases should be ruled out at the time of diagnosis. In cases of vaginal discharge with a large number of basal cells and leukocytes, trichomonas infection and Candida infection should be excluded. In cases of bloody discharge, attention should be paid to exclude malignant tumors of the genital tract, often requiring cervical smear and segmental diagnostic scraping. The possibility of co-existence of inflammatory and malignant lesions should be noted. 4. Endometrial inflammation with pus accumulation in the uterine cavity is characterized by increased vaginal discharge, which is plasma or pus-blood, often accompanied by fever and vague pain in the lower abdomen. On examination, we can see that the uterus is enlarged, soft and painful, and pus can be seen by dilating the cervical opening. The pathological results of scraping were free of cancer cells. Anti-infection treatment was effective. 5.Submucosal fibroids, endometrial polyps, cervical polyps: submucosal fibroids and endometrial polyps can show bloody or pus-blood discharge. Diagnostic curettage and hysteroscopy-guided biopsy can identify them. Chronic inflammatory stimulation causes local mucosal hyperplasia of the cervical canal and gradually protrudes towards the ectocervix to form cervical polyps. The polyps are mostly red tongue-shaped, one or more, and bleed easily when touched. The vaginal discharge is increased and may be bloody. It may be accompanied by lumbosacral pain and lower abdominal cramps. Ultrasonography, hysteroscopy and segmental scraping can help to confirm the diagnosis. 6.Postmenopausal endometrial hyperplasia is divided into simple hyperplasia, complex hyperplasia and atypical hyperplasia, of which atypical hyperplasia belongs to the category of precancerous lesions. Diagnostic scraping can be performed to differentiate them, and close attention should be paid to follow-up. 7.Other gynecological malignant tumors such as cervical canal cancer, uterine sarcoma and fallopian tube cancer can be manifested as vaginal bleeding and fluid, lower abdominal pain and palpable mass in the abdomen. Segmental scraping and B-mode ultrasonography can assist in the differential diagnosis. Postmenopausal vaginal bleeding should not be treated carelessly, but should be treated promptly by a doctor to identify the cause. Routine gynecologic examinations can be performed to detect Trichomonas and Candida, and preferably cervical cytology smears. Ultrasonography is routinely performed to check the thickness and echogenicity of the endometrium. Diagnostic curettage is performed to confirm the hyperplasia of the endometrium. If cervical polyps are present, they are removed under aseptic conditions and sent for pathological examination. In case of endometrial inflammation, anti-infective treatment should be noted. For patients who are not diagnosed by ultrasound and diagnostic scraping, hysteroscopy and biopsy are recommended to clarify the diagnosis. Once diagnosed, patients with endometrial cancer should be hospitalized. Treatment should be comprehensive and mainly surgical. For patients with advanced stage and those who cannot tolerate surgery, radiotherapy, chemotherapy and hormone therapy are used. Patients with other malignant tumors should also be hospitalized for surgery, radiotherapy or chemotherapy once diagnosed. Treatment of senile vaginitis is done with topical or systemic supplemental estrogen and vaginal metronidazole. Cervical polyps are removed and sent for pathology. Regular follow-up should be noted in patients with endometrial hyperplasia found by diagnostic curettage. In older patients with pathological diagnosis of atypical hyperplasia, hysterectomy is recommended to prevent malignant transformation of the disease.