When TTC or during pregnancy, are/were you immune to Rubella? Meaning did you get a shot 6 months or before, prior to TTC?

Reading up on vaccinations.. Rubella vaccination is only for child bearing aged females (for the most part) specifically so you don't get it while pregnant as it could cause birth defects and such. I'd love to know - if INFANTS are MADE to get this shot, and it wares off 20 years later... why on earth aren't doctors pushing to keep everyone's vaccines up to date, adults included. I see no pressure whatsoever- in fact when I was TTC for 1.5 years I was never asked about any of my immunizations and I'm 32. I got checked 2-3 years prior to make sure things were in working order to TTC and still no questions.