When I was in high school, I know there was a stigma with it. Isn't there a stigma with everything in high school? ;)
When I was in college and while I was working on my doctorate, the number of American women in my classes got smaller and smaller the higher up it went. However, my mentor was an American female. She was great. I got to know many wonderful mathematicians from other countries, both female and male.
Perhaps you were fortunate and went to a good school that encouraged women in Math.