contrary to popular belief, breastfeeding does not cause a woman's breasts to sag. pregnancy does. okay, i'm over-simplifying a tad because actually gravity, smoking, bmi, and aging also contribute to breast ptosis (the technical term for sagging). and here's an interesting tidbit, resesarch has shown that high-impact activities like jogging and running may actually cause more stress to the ligaments of breasts than pregnancy. and, silicone breasts, because of their weight, cause the most stress (during high-impact activity) with the result that the breasts sag in a shorter time than natural breasts of the same size. so, maybe there's something to be said for the au natural sedentary lifestyle. if so, i'm all set.
but back to the subject at hand, the fact remains that if a woman is pregnant the stretching is already done. so, hopefully she will not shy away from breastfeeding because breast truly is best for baby.
if a woman knows that she or her spouse are going to be particularly conscious about perkiness, it may be a good idea for that couple to consider adoption. because adoptive breastfeeding is possible, and it won't alter breast appearance either.