Hi, my husband has this (only discovered last year). Most of the time it corrects itself after birth so don't be too worried, they'll just do regular US to keep an eye on it, and give you some advice about what to look out for as any indicators of any probs.

If bubs continues to have probs afterwards post again, as then I can fill you in on our story about kidneys!!! Don't worry, it has a happy ending!!