I wouldn't. DS2 had one, and while definitely weird to hear tummy rumblings through a golf ball sized belly button, it was not really anything to worry about. It was the biggest around 2 months of age, then started shrinking again. I forget when it quit being noticeable, they generally close up on their own in the first couple years. They are not usually anything to worry about!

Oh, Dr. Sears talks about this in The Baby Book, too.