Urine pregnancy test negative but pregnancy confirmed, what is the cause?

Patient: Im 4 months pregnant but I dont feel like I am. According ro my doctor I got pregnant during my period but before I got my period I took two pregnacy test. They were both negative. What are the chances that I got pregnant before I got my period?

Doctor: The efficacy of a urine pregnancy test depends on the timing of the test. Urine pregnancy tests are most accurate when d one when you missed your periods of after 2-3 weeks of the sexual act. It might be that in your case the level of the pregnancy hormone may be to little to be detected in the urine at the time of the test.