Hello and welcome to HCM. Thank you for your query. The reason why an UTI exists despite treatment for long duration s of time are the following: 1. Inadequate dosage of treatment with antibiotic therapy 2. Inadequate duration of antibiotic therapy 3. Inappropriate antibiotic used 4. Underlying cause, that is causing the UTI. In such cases even if the UTI is treated and is regressing, the underlying cause leads to a flare-up again Let me help you by listing the appropriate measures to tackle each of these possibilities. They are: 1. Discuss the proper dosage of the antibiotic, suitable for your age and requirement 2. Discuss the adequate duration of antibiotic therapy with your treating doctor 3. Get a urine culture test, this will help in providing the doctor information on the antibiotic which is most suitable to treat your condition 4. Conduct more elaborate investigations to find the underlying cause. A physical examination by a urologist or a gynecologist. An abdominal and pelvic ultrasound. A vaginal and uterine swab to be sent to the laboratory. Causes for vaginal bleeding are: polyps, uterine fibroids, ectopic pregnancies, menopause, miscarriage, contraceptive insertion, etc. Please consult the doctor under whose supervision you have started the birth control, and also go about an elaborate examination. I hope I have succeeded in providing the information you were looking for. Please feel free to write back to me for any further clarifications. I would gladly help you. Best wishes.