I used to get them fairly frequently, including at the beginning of my first pregnancy when my so helpful OB made the comment: "It will probably go away by the end of the first trimester, but if not then it could be malignant." Gee, wasn't that nice to have to worry about along with everything else for a couple of months.

With all of mine I was told to wait for a cycle then come back in for another ultrasound. It had always disappeared by that time.