No more ultrasounds?

mrs.forrister

I'm a FTM and had our 20 week u/s on Monday and all looked perfect.  I asked the nurse if I would be getting any more u/s and she said only if they hear something wrong in the heartbeat, if I'm not measuring right (too big/too small) or if I go one day past my due date.  I just thought they'd do at least one more u/s before delivery.  She said it was for insurance purposes.  Is this normal?