Word 2003 mail merge – If…Then question

I’m using Word 2003 with an Excel spreadsheet as my data source to create a merge in a lengthy document. I need an If…Then-type field that will allow me to have another field code in the Insert This Text area.

Example:

If: “Spouse_Y_N” Is Equal to: “Yes”, then insert: <>.

Any ideas on how I can achieve this?

Thanks in advance.