Whether or not your implants will affect how your breast functions depends in large part to where your incisions are and whether any milk ducts or nerves were cut. If the incision is in the fold under your breast or near the armpits, then chances are the ducts and nerves around the nipple were not affected. If the incision is around the areola (the dark area around the nipple), then those important nerves and ducts may have been severed. If they have been severed, then your chances of being able to fully breastfeed your baby are decreased significantly.

It is important that you learn as much about breastfeeding ahead of time as you can--learn proper positioning, the signs of good feedings, counting diapers as a way of telling how much milk is going in. After your baby is born, put him to your breast as often as he will go, and see what happens.

As for the safety of nursing with implants, the concern has been whether the silicone might leak out and get into the milk. There have been only two case studies that seemed to suggest a potential problem for the babies who nurse from breasts with these implants, and in both cases the data was inconclusive as to the true cause of the problems. Most experts consider these breast implants to be compatible with breastfeeding, and that the benefits of breastfeeding far outweigh any risk of problems.

Silicone is a very large molecule and doesn't dissolve in water, so the chances of it leaking into the mother's milk are very slim indeed. And there are no agreed upon standard acceptible levels of silicone that would make testing of the milk useful. There are other sources of silicone besides the breast implant, including the ingredients in an over-the-counter gas reducing solution commonly given to infants. So even if you could measure your levels of silicone, there is no way to know what the source of that silicone is.