Congratulations on the delivery of your little one and way to go on starting exercise. Each woman's post pregnancy weight loss journey is unique, but if you stick with healthy habits you'll successfully lose the weight while breastfeeding.
1 lb per week is a great goal. It might feel slower than you'd like, but it is sustainable and that what is most important.
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Getting back to your Pre-Pregnancy Weight While Breastfeeding for more information from BabyFit.com.