Hey I Was Wondering How Do I Get Weed Out

Hey I was wondering how do I get weed out of my system? Before I found out I was pregnant I was smoking real heavy I found out when I was 5weeks and still continued smoking until I was close to 7weeks I quit completely after that and been around every since because my boyfriend and other family members do it, I'm 16weeks now and trying to figure out why isn't my system clean by now.