Ally Sheedy was 17 in I Think I'm Having A Baby when she played the character 'Cathy'.
That was over 43 years ago in 1981.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 61, and has starred in 72 movies in total, 72 of those since I Think I'm Having A Baby was released.
In I Think I'm Having A Baby, I think Ally Sheedy looks: