Cyst on Umbilical Cord 33 weeks

megwv3

At my 33 week growth scan, my MFM said there was a cyst on the umbilical cord. There wasn't one mentioned two weeks prior when I had an ultrasound done. She's measuring fine. Her weight is a little over 4 lbs which he said was good. He didn't seem concerned at all. It's rechecked in 3 weeks. However, how can I not worry? There's something on the cord. That's worrisome. I know that it could be signs of genetic abnormalities but we had testing and that's normally found in the first and second trimesters. Not just popping up in the third. Has anyone else had this or know any more information about it?