There is a situation in which we believe a baby is born above or below
their genetically-determined best birth weight, and it corrects itself.  Of
course this is a dangerous area to play in, because one could say (falsely)
that all babies who fell off the curve belonged in this category.  Still,
if he was so unusually large to begin with (you say the mother did not have
gestational diabetes?), and he is now closer to "average," one would want
to chart his weight changes since birth to see what is happening now.  Is
he gaining at a good rate?  Has he plateaued, or is he losing?  The picture
of what he's doing now will shed light on this situation which just looking
at the birthweight may not do.  The abundance of output is certainly a good
sign, although I had a mother once whose baby had tons of output and failed
to thrive because of an overdosage of pituitary medicine (given to the baby
to compensate for an inherited defect).  The physician had trouble
believing the medicine, and not the breastmilk, was at fault until we
weighed the input (baby pre- and post-feeds) and the output (all those
weight and poopy diapers--and there were upwards of 14 soaking wet diapers
a day in this newborn!) The baby began to gain weight once the medication
dosage was adjusted.

One wonders also if any factors in the terminal phase of pregnancy (for
instance, labor meds) could have caused a temporary weight gain (since you
are considering edema).  Maybe someone more knowledgeable can address this
question?

Arly

[log in to unmask] (Arly Helm, MS, CLE, IBCLC)