Worried

I’m just about 31 weeks. We’ve had a couple ultrasound confirming our sons kidneys are dilated. It’s started with just the left and has now moved to his right. We have been referred to a pediatric urologist to prepare for his birth. Last week at 30 weeks we had some decreased fetal movement and a NST was ordered and fluid check. It seems he has on the higher end of fluid and is measuring about 2 weeks bigger at 4+lbs. I scheduled my c section at 39 weeks 4 due to the holiday. I’ve never made it passed 38 weeks with my previous 3 pregnancies. I worry because the perinatal specialist said it’s best not to go in to labor but doesn’t recommend delivery before 39 weeks it’s so confusing to me.