My amniotic fluid level is low, has this happened to anyone else?

I'm almost 37 weeks and I spent all last night in the hospital. They said my fluid level should be at a 10 and I was almost a 4. So I was on IVs all night and was released today. I have a follow up with my doctor tomorrow and the hospital said if my fluid lev doesn't stay up I would have to deliver. Has this happened to anyone else? What was the outcome?