I've been puzzling over this a little and find myself wondering several
things:

1.  If infant intake stays pretty level from 1-6 months, what about fat
content of milk?  Is it dynamic and changing during this time or does
the milk's composition remain the same also? Has anyone looked at milk
composition over this period of time?  Doesn't frequency of breast
emptying influence milkfat content?  Could it be that baby's increased
nursing spells are a trigger to reset milkfat content?  ie, the baby
needs increased energy intake so increases nursing frequency to increase
milkfat?

2.  When women experience the drop in milk production while pumping, is
it in anyway related to their frequency of pumping?  Having not worked
with long-term pumpers I have no personal knowledge--how about it some
of you NICU or pump rental people?  I don't remember having "growth
spurt" nursing with any of my three.  There were times when they were
fussy and wanted to nurse, but we sort of did the sip and snack type
nursing a lot, as I "wore" them til they were getting around on their
own.  I've been aware of the need to counsel moms that this may occur,
and know moms who have been under the belief that they didn't have
enough milk because baby wanted to nurse more frequently.  But in my
experience, those moms were less inclined to allow truly on demand
nursing, wanting baby to feed and then let mom get on to her other
responsibilities, until the next feeding time.  They don't seem to be
happy with cluster feeding behavior, and are inclined to interpret such
behavior as a milk supply problem.  Old insecurity demon raises it head
again.  and many of them seem to be trying to get baby to wait longer
periods between feedings as the baby gets older.

3.  What effect does milk storage capacity have on this whole thing?  If
frequency of feeding sets milkfat content are there differences in the
way the breast responds to frequency based upon the breast storage
capacity?  ie, does mom with small storage capacity respond less to
frequency than does the mom with larger capacity?   How does baby of mom
with large capacity reset the milkfat content?  Are these babies
"doomed" to a life of large quantities of lowfat milk?

Oh dear, getting too late and I can't seem to think as clearly as I
should re all of this.  I'd love to see more discussion of this, as I
don't get much chance to talk with other LC-types about this lactation
science type of stuff.

Melinda Hoskins, MS, RN, LC2B
In Northern Nevada, where I've had a positive breastfeeding day!