Powerpoint slides into a Word document - how to keep file size down ?

I hope someone can help me....
I'm trying to put together several training courses. The student books will be Word documents, but there are already many Powerpoint slide shows to be included in the books. When I use Powerpoint's File - Send to - Word feature, and then insert the new Word file into the student book, the student book file ends up ENORMOUS - 47 MB and still growing. This is very slow to access, and I can't e-mail it (important - my training colleagues are all over the world).
Can anyone suggest a way to reduce the size of the Word file, whilst still keeping the slides in there ?
Many thanks.

Nansi Jarvis