There is an entity called "physiologic anemia", which hits its low point
at about 3 months of age.  We used to say that for a full term baby this
low point was as low as 9.5 g%.  For a premature baby, you could go as
low as 7.5g% at about three months.  It is possible that premature
babies had this low a hemoglobin because they often had a lot of blood
taken.  There has been some changing of opinion from time to time, but
the fact remains that it is normal for the baby's hemoglobin to "bottom
out" around three months after birth, and then it starts to rise again.
Tests that were done showed that the babies were *not* iron deficient,
and, in fact, their hemoglobins came up later.

A hemoglobin of 10 g% at 3 months, seems to me of no concern at all.  A
hemoglobin of 8g% at 3 months may be.  But I think it worthwhile to
watch and wait if these babies are healthy otherwise.

Jack Newman, MD, FRCPC