Not sure what platform you are using.
I am recreating a WordPress site from a Joomla site, (complete reconstruction obviously) and the client's site is over 100 pages.
It is doing fine on the host however I believe that with WordPress, it more depends on the power of the host, (what level of plan you have and if more expensive, provides more power and speed). Then graphics and image size can slow it down. One of the most important things that can slow a WordPress site is too many plugins.
Hope this helps