My son was born in St.Teresa's Hospital. My doctor was afraid that he did not have enough water input. So, my son drank Enfamil during our staying in the hospital. My milk supply was not good at the beginning. When I returned home(after 3 days), I insisted to feed my boy with my milk totally, though he was fed on formular originally. I believe if we insist, we can breastfeed our beloved baby totally, just what I'm doing now( He is now 4.5 months old)