Settings API

I’m using the WordPress Settings API to create an options page for a plugin that handles images and links. I can register 3 add_settings_field calls and add 3 images and links to the site and it saves no problem. The problem is, Sometimes I want to have 2 sometimes 4, etc. Does anyone know of a way to dynamically let the user add a new field (add_settings_field) on the fly. For instance if it started with 1 field, but they needed a second for another picture.