Here's a link to a site showing ultrasound images of retained POC (products of conception)

Spontaneous abortion - Retained products of conception

Here's a link which explains how to read ultrasound images of the uterus.

My scan today showed something in the upper part of the uterus but my RE said it wasn't there last time so it is likely just some clots. I sure hope so. I'm ready to be done now.