The actual physical stimulation may be the cause of the urinary frequency after the intercourse, the male urinary frequency after the intercourse may be the urethritis, the prostatitis and so on the disease causes, the female urinary frequency after the intercourse may be the urethritis, the pelvic inflammation and so on the disease causes. 1. Physical stimulation: Because the female urethra is close to the vagina, the male urethra is in the front of the penis, if the action is larger or more frequent during intercourse, it may stimulate the urethra, and frequent urination occurs. 2. Urethritis: Because the urethra of both men and women will stimulate each other during intercourse, if a man or a woman suffers from urethritis, it may lead to frequent urination after intercourse. The cause of urethritis may be related to gonococcus, Mycoplasma genitalium, Trichomonas vaginalis, Chlamydia trachomatis and other pathogenic bacterial infections. Patients will have symptoms such as frequent urination, urgency, redness and swelling of the urethral opening, and painful urination. 3. Prostatitis: Frequent urination after intercourse may be caused by prostatitis in male patients. The cause of prostatitis may be related to pathogen infection, urinary dysfunction and other factors, irregular sex life, poor dietary habits and other reasons may also trigger the disease. Patients will experience burning pain in the urethra, frequent urination, incomplete urination, fever and other symptoms. 4. Pelvic inflammatory disease: Frequent urination after intercourse may be caused by pelvic inflammatory disease in female patients. The cause of pelvic inflammatory disease is mainly related to Chlamydia trachomatis, Staphylococcus aureus and other pathogen infections. Patients will have lower abdominal pain, increased vaginal discharge and other symptoms, accompanied by frequent urination, urination difficulties and other phenomena. If frequent urination after coitus occurs, after excluding physical stimuli, it is recommended to go to a regular hospital for examination to clarify the cause.