I had three c-sections and was able to lose all the weight all three times. It was hard to get started, because your tummy is sooooo delicate for such a long time. I mean, your stomach muscles were just severed! It's a routine surgery, yes, but very invasive.
So, start slowly. I started by laying on the floor and just flexing my toes. I did this from about 8 weeks post-op. Then, as my stomach strength increased, I started just barely lifting my head off the floor, then alternated by lifting my feet off the floor, just for a few seconds. This continued to build my strength.
I also walked on a treadmill with weights in my hands, lifting the weights over my head and walking like that for a while.
To keep the weight off, I work out three nights a week, 20 minutes on an elliptical, followed by a series of push-ups, sit ups and leg lifts. I also try to be active, shoveling snow, gardening, things like that. I still have some extra skin on my belly, but I'm okay with that. It's my badge of honor for giving birth to three kids!
Of course, you have to limit your food intake. If you are breast-feeding, you can't limit too much. But you can definitely limit your sugar intake. Watch out for sodas, energy drinks, and specialty coffees. They can have so many calories.
Even diet sodas are shown to not help with weight loss because they trick your body into thinking it's getting something sweet and it spikes your blood sugar anyway.
Hope this helps.
http://keystosimpleliving.com/health_exercise.php