MS Word Bullets & Numbering

While using numbering of paragraphs I found that the first paragraph numbered 1) that ends on the first page uses the font and size (12)I want. But upon numbering the next paragraphs (2,3 & 4) on the next page the size of the font changes to (10). Ihave tried all the suggested MS help situations without success. Then for no apparent reason the next paragraph numbers (5,6,etc) revert back to size 12. Any suggestions would be appreciated.