I think mine started around the time I was born. LOL. Even at 5-6 years old I'd go upstairs and forget what I was up there for. I think my DH is worse than I am, he asks me the same question several times and can never remember the answer, so then he gets hormonal answers, poor love.

So it set in for me early, before I knew I was pg I'd write something down and then completely forget why I'd written that and the phone number 3-4 minutes after I hung up the phone. Ah well, at least I can blame preg-head now!