Susan,

I usually tell moms that the full-term, healthy breastfed baby does not need
iron supplements.  The baby has iron stores from birth (best if cord isn't
cut too soon) which is complemented with the iron from breastmilk.  Although
breastmilk has less iron than iron fortified abm or cereals, it is more
easily absorbed by baby; therefore, the baby gets more---about 49-50% is
absorbed from breastmilk as compared to about 4% from abm.  It is my
understanding that iron supplements will interfere with the baby's ability to
absorb iron from breastmilk.
Once baby starts solids, foods naturally rich in iron are suggested.

My own children never had iron or vitamin supplements.  My oldest did not
start solids until 11 months.  There was never a problem with iron
deficiency.

Hope this helps.

Aloha,
Gloria Thai  LLLLeader Hawai'i