Quite frankly, many women never do get back to their previous weight or their previous level of fitness. That doesn't mean it can't be done. It's just that with the new responsibilities as a mother, there is less time and less energy for physical fitness.

In a recent study of healthy, adult women fitness, strength, and activity were measured before and after pregnancy. Less than one per cent returned to their previous level of fitness. Loss in strength was not fully regained after 27 weeks postpartum when the study ended.

Further studies are needed to find out how long it takes to return to a pre-pregnancy level of fitness.