My DD2 also had this but also had low Papp-a which can cause small babies and prematurity. DD was born at 37wks because scans said she had stopped growing. Hard to know whether it was the cord or the low papp-a that caused it and it is even debateable whether the scan was accurate as she was bigger (thankfully) than the scan predicted) - she was 2.4kg.

As already mentioned you will have a follow up renal/kidney scan but all should be ok.