ms word 2013 massively increases file size of images inserted into new word document

I've compressed a lot of pngs in gimp using a web optimised palette. When these are saved in word whether as .doc or html the images are increased in size eg from 12kb to 99kb. The only work around I can think of is to manually rename all original images (to match names given by Word) and put them into the associated html folder in place of the corrupted images. Any tips much appreciated.

Recent Questions...