Save the date for Baby Shower?

Sim
Few years back I moved from So Cal to Nor Cal and now I have friends and family in both reigons of CA. I'm planning on having my babyshower during early Dec, but due to holidays and kids exams I don't know how many people will be able to come. I want to send out save the date for my baby shower and find out how many people will actually show up. That way I can choose the venue accordingly.
Is it normal to send out save the date for a baby shower or is it tacky?