Losing Mucus Plug

So I know discharging mucus is totally normal but I've been losing a lot more lately. I'll be 30 weeks this week and literally everytime I've gone to the bathroom and wiped I've discharged mucus. Like I've had it happened before, but not this much in one day, usually every so often. I have an appointment on Wednesday but I wanted to know if anyone knew why this happens and if I should be concerned about how much it's happening?