Pelvic effusion with hot water bags is not useful, patients need to go to the gynecology department for a detailed examination, according to the specific circumstances to take targeted treatment. Pelvic effusion is a clinical manifestation under ultrasound, there can be a small amount of fluid in the normal pelvis, which is a normal physiological phenomenon, not a disease, if the deep diameter of pelvic effusion exceeds 3cm, it can be pathological, the patient will have pain in the waist and lower abdomen, falling sensation, menstrual disorders, infertility and other symptoms. Usually, when patients experience pain in the lower back and abdomen, they will want to use hot water bags to apply hot compresses to relieve the symptoms. However, this cramping sensation is due to chronic inflammation leading to scar adhesions and pelvic congestion and cannot be relieved by external hot compresses. Patients should go to the hospital for timely examination to observe the abdominal fluid, and also to identify the cause before deciding on the treatment plan, so as not to blindly adopt an ineffective treatment to avoid delaying the condition. Usually, physiological pelvic fluid does not require special treatment, and a small amount of fluid can be absorbed on its own. If the pelvic effusion is caused by pelvic inflammatory disease, tumor and other disease factors, treatment should be carried out according to the cause.