Hello, and i hope I can help you today. Unfortunately, marijuana can be detected in your system for even up to four weeks after use. There is no way to cleanse it out of your body, but the sooner you stop smoking, the sooner you will test negative. Even if you live in a state where marijuana smoking is legal, use during pregnancy is still not advised due to a lack of long-term data on the effects it will have on the baby. In the United States, you have to give consent to be tested for drugs, so no one can test you without your permission. However, your baby can be tested without your permission if there are any indications of withdrawal symptoms or the the baby s doctors otherwise suspect drug exposure. However, even if you have a positive drug screen, that does not mean your baby will be taken away from you... But a social worker would likely need you to repeat the test until it becomes negative and demonstrate that your baby is not at continued risk for exposure. So again, there is no way to cleanse your body of marijuana other than not using it and waiting. If you have your baby soon, and he/she is healthy, there is no reason you or the baby would be tested unless you had other reasons for your providers to suspect drug abuse. I hope I was able to adequately answer your question today and that my advice was helpful. Best wishes for the rest of the pregnancy, Dr. Brown