I wanted to give you a nice update.. today I went back for my 32 week ultrasound. Baby's kidneys are just fine, no dilation at all. The tech said she sees it all the time at 20 week scan then its gone by later times. Good luck. I hope and pray this is how it goes for you and your LO as well! :)
I am going through this exact same thing right now. At my 20 week anatomy scan they told us that one of our son's kidneys is dilated. I have another scan next week.. I'll be 32 weeks. She did say that it could be nothing at all, that maybe the baby just had urine in his bladder. She also said that if it still dilated, a lot of the time after the baby is born it will work itself out. She said worst case scenario if baby is born and kidney is still dilated, they wait until they're around a year and check it again and if at that point it's STILL dilated, they do some kind of little surgery, put a little stint in there, but it's no big deal. Whatever you do, DO NOT GOOGLE THIS. I promise you it isn't worth it. I posted on this forum and no one answered so I started googling and all it did was make me feel awful. Honestly, if I was you, I would not worry a wink about it. Like I said worst case scenario is a little surgery down the road that is absolutely no big deal, and best case, which it probably is, baby just had to pee. Good luck!
I went through this when i was pregnant with baby girl. One of her kidneys was dialated but by the next ultrasound they were fine. She is 3 weeks old now and perfectly healthy. Dont worry, she may just had to pee