Katee Sackhoff was 16 in Fifteen and Pregnant when she played the character 'Karen Gotatus'.
That was over 26 years ago in 1998.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 44, and has starred in 26 movies in total, 24 of those since Fifteen and Pregnant was released.
In Fifteen and Pregnant, I think Katee Sackhoff looks: