The main cause of pain in the urethra in women after sex is the possibility of a urinary tract infection. Because the female urinary tract is relatively straight and short, it is easy to cause retrograde infection during sex. The main infecting bacteria is Escherichia coli, which is a relatively common pathogenic bacterium that causes frequent, urgent and painful urination in women, and in severe cases, even hematuria. Generally this condition can be clearly diagnosed by urinalysis and ultrasound, and according to the results of the urine analysis drug sensitivity test, apply sensitive antibiotics for treatment. The course of treatment is usually about 7 days, and you need to drink a lot of water so that it can be effectively cured. After the symptoms have disappeared, the urinalysis will be repeated to determine whether the disease is cured.