Hello, I understand your concern. Congratulations on your pregnancy. First of all, I recommend you stop smoking altogether, as effects of weed on the fetus have not yet been thoroughly studied, so better to be on the safe side. Besides, if you want to clear your urine of THC as fast as possible, the sooner you stop smoking it the better. The time it takes for THC to leave your body depends on many factors, such as age, body mass, metabolism rate. In pregnancy, the metabolic rate is higher than normal, so this works in favor of faster clearance. Also, good hydration helps speed up the process. Make sure you feed your increased appetite with healthy food instead of fast sugars and processed foods. Wishing you all the best. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Ornela Ademovi