What is the best way to get a flat tummy again, after childbirth?

Trim the waist!: Keep your abdominal and posterior core muscles toned with repetitive activities and resistance. If you are pear shaped, less calories in versus out will cause weight loss, which together with firming and toning exercises, will make you look as close as is possible-and that is close: apples (high waist, weight on center tendency) need to exercise as above and cut carbs to prevent internal "gut.".

Time and fitness: It can take awhile for the skin and other soft tissues to firm back up. Returning to pre-pregnancy weight can take time- though breast feeding and regular aerobic activity can help. Abdominal exercises can help tone the underlying muscles.