A single renal cyst is a benign condition, which resolves itself, usually without intervention or complications.
The Doctor (Perinatologist) will perform tests to rule out the presence of multiple cysts, renal abnormalities or obstruction related to the known cyst.
It is useless to say don't worry, I know, but I hope you can focus, for now on the possibility of a benign simple cyst.
I will be happy to answer any further questions you have now, or questions that arise, regarding tests, etc. Good luck to you.
I hope my information is helpful. If you have more questions, just ask! I will gladly help, otherwise please click "accept".
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