I remember measuring myself late in my pregnancy. I was 35" for all three measurements (bust, waist, hips). I was impressed with how big I was! Wouldn't I like to be 35" now for two of the measurements! I weighed 132 and 134 at the very end of my pregnancies. The only size that permanently increased, was my shoe size. I breast fed both babies. That was back in the day when BF was just coming back into "style" again. Within weeks of delivery, I was back to my starting weight, or less. My point is, it wasn't pregnancy, breast feeding or anything else related to reproduction that made me fat. It was from eating too much and exercising to little.
I am lucky that I grew up in a time when it was not considered necessary to be stick thin. In fact, there was a long time in my young life when I thought I was too thin. I still have trouble thinking of myself as a fat person.