Milk production is will determine the total glandural tissue in the breast and baby's appetite later.. and of course, the ability of breastfeeding for the mother. Fat.. in this case that provides round breast shape and protects the internal structures from injury. They do need a nursing bras for large breasts. Although, the amount of fat tissue and breast size is not at all directly related to the ability to produce milk for their children.
Caring for a baby can provide special challenges for mothers who have advantages in the form of their breasts, but... with proper preparation and training, there is no reason why you can not have a very successful breastfeeding experience regardless of size or shape of your breasts.