How to notify of scroll in iframe

For the sake of screen readers such as JAWS, etc.

Given a list of navigation options which are a collection of documents and locations within them, when one is selected the iframe will load and/or 'scroll' to the selected document and/or location.

A sighted person can see the effects of their selection, but how might one effectively provided the means to a screen reader to notify the user of the effects of their selection?

If the best that can be done is some explanation prior to list of options (and perhaps a reference to the iframe as being the recipient of the change,) what means might effectively provide means for the user to jump reading to the navigated location?