Does a Danes period change their behavior?

Hey chat, I have a sweet female Great Dane her name is beetle and she’s 11 months old, around 75 pounds ? And when she stands on her hind legs she’s around 5’2. she just got her first period and I just have a couple questions on what next steps to take. I heard that fixing your female dog before their first period can stunt their growth or cause health complications down the line so I was waiting to do it, would it be a good idea to do it immediately after she’s done or should I wait for her to go through a few more ? Also she’s always been super nice around other dogs very gentle and playful despite her size lol I’m just concerned that after going through her period she might become reactive or more rebellious than she already is. Any advice ?