Selecting the correct records for mailing labels based on SQL Serverview

I need to print some mailing labels. I work with an adp Access
frontend and a SQL Server backend.

The problem is this: I need to print address labels for all the people
whose birthday falls within a given month.

So far I have a SQL Server view that generates the names, addresses,
and birthday months (e.g. 1, 2, 3, ...) for the people I need to send
mail to.
I have a report for the labels that is based on this view and includes
the name and address.
I have a form that brings up the label report in preview mode. On this
form I have a combo box that allows the user to specify the birthday
month for which they want to print the labels.
So far my label report just brings up everybody who is included in
that view.

My question is the following: The user will use the form's combo box
to select the birthday month for which they want to print the labels.
How can I set up my report to accept this value as a parameter and to
only print the names and address associated with this month?

Thank you for your help.