Hi,
Welcome to the ehealthforum. I am glad to help you out. Normal discharge during pregnancy is thin, white, milky and mild smelling. If you are having green yellow discharge then it may indicate vaginal infection which needs to be properly managed. I suggest you to get it evaluated from a gynecologist and get a vaginal smear of the discharge done.
Some vaginal infections (though not all) may be associated with preterm labor or problematic births, and it's important to diagnose and treat them before complications develop.
I sincerely hope that helps. Take care.