Since the implants are placed behind breast tissue – or behind breast tissue and muscle – your ability to breast feed would not be impaired by the implants. In fact, the breast tissue itself is barely disturbed during the breast augmentation procedure itself.
What might change would be your breast shape. Everyone is different in how well their skin retracts after pregnancy and breast feeding. If the shape after feeding is not to your liking, then a breast lift (mastopexy) may be indicated.