Usualy the mucus plug is brownish in color, not yellow or
green. Any time you have a yellow or
green discharge, it is a sign of infection. Think about, anytime we have a yellow or green discharge from anywhere in our bodies, it's infection. You SHOULD call your Dr ASAP. If you are 39 weeks, it is about time to domino and if you do have infection you might need treatment before birth. One of the other ladies weeks ago had a similar situation and she went into labor just a few days later.