We had the same thing picked up in a scan on Tuesday. Google is a very, very scary thing in this case, and all I can say (after learning the hard way) is that you should leave google alone and wait until you can discuss the implications with your OB.

I did the same thing - googled and freaked myself out pretty majorly. While it MAY indicate problems with heart and kidneys and a few other things, it doesn't guarantee problems at all. Most of the scarier things it can indicate would have been ruled out in the 12 week scan or in the rest of your 18 week scan. At least that was the case for us.

We've been told we have to have another scan at 24 weeks to check the little one's heart more closely, and another scan at 32 weeks to check on growth. My OB told us that these were just precautions and that things looked great so far so further problems are unlikely to occur, we should just think of it as more opportunities to see our little one before birth.

It can mean that your baby will arrive a little early and a little on the small side of things, but a friend's baby had the same thing... he arrived at 36 weeks and is now a happy, healthy 2 year old with no further problems.

I hope this helps put your mind at ease.

BW