The answer is yes.....and sometimes no. This horribly unhelpful answer is the truth in part because of how hard it is to define the term natural. Like beauty, a perfectly natural result is really in the eye of the beholder and therefore essentially a relative term. What may be considered a very perfect and natural breast augmentation result for one person may be viewed as poor and quite obviously unnatural to another.
With that disclaimer aside there are a number of ways a breast augmentation can be made to look as natural as possible.