Is it even worth working out?

I had my daughter a little over 4 months ago and am down to less than pre-pregnancy weight. I started working out a few days ago and It has kind of crossed my mind is it worth it? My husband and I want to try for another baby in 9months to a year. I never gained weight during my previous pregnancy I lost up until the last 2 weeks I gained half of what I had lost back. Now I'm less then pre-pregnancy last time. I know it would tone me up more I am not a skinny individual but I guess I just need some inputs?