You will need to share your PROC REPORT code - reply to your post and paste the SAS log generated output with source code totally revealed. Or, the other option is to start by self-diagnosis and removing some of your SAS code until the blank page no longer appears, then reply to the forum with your more specific problem condition.
As this note http://support.sas.com/kb/16/976.html
"When using ODS to create RTF files, SAS creates one or more tables in RTF, then hands those tables off to MS Word to paginate. In some cases, a table is just close enough to the bottom margin that MS Word thinks there is more information for that table to continue on the next page, and generates a blank page at the end of the document, with titles and footnotes populated.
There is not anything SAS can do to guarantee that MS Word will not think there is just enough information to build a new page.
Try adjusting the margins for the RTF file, as discussed in SAS Note 24033."