I am so glad you stop smoking pot, very proud of you. But everything you put into your system after the 20th week of pregnancy will be picked up in the baby's meconium (poop), if they should test it. Good luck.
As long as you remain abstinent you will not test positive after a short period. Marijuana hits fat cells strongly and will remain detectable for as long as a month and more. Every body is different and there will be some differences in that respect - - - Be safe and best of luck (along with congratulations!) - - -