Peter Hartmann's work (see two articles in JLH March 1995)) discusses the
mechanism of milking frequency in dairy animals as being one of the
mechanisms which drives milk production. He also cites a study in goats
which describes milk decreases if udders are not fully emptyied. I have
always been extremely interested in the bovine literature, because there has
been a whole lot more study (sad to say) of milk productiion in herd animals
than in women.  Just another way medical science has ignored and by-passed
the needs/concerns of half the human race. Anyway, as we are all mammals,
there are more likely in my opinion to be similarities rather than not.

Hartmann also points out that the 800 mL/24h figure is an average peak milk
production figure --   just a number.  He cites reaearch (Dewey, Lonnerdahl
and others) showing many women producing lots more milk (for twins or trips
or tandemly nursed singletons.)  His point is that the milk production
capability of the individ. woman greatly exceeds the intake needs of the
average infant.  Thus it is the infant's demand signaled by its ability to
drain the breast which drives milk production. Along with, of course,
hormonal/physiological maternal issues.

 I found interesting the post (from Lisa M?) hypothesizing that too few
feeds during the 1st 3 months may calibrate breasts at too low a level so
that they respond ineffectually to autocrine control in the  beyond-3-mo.
phase of mature lactation.  I  wonder if another factor might be that some
infants are immature and feed poorly/drive poor initial calibration, setting
"thermostat too low" and then begin to grow, thrive, improve, alter ability
to suck, whatever, and sort of "wake up" to find milk supply is too low to
sustain the kind of growth they are now ready for. This might make them
really unhappy, because we all know that the period of really rapid growth
in human infants is during the first 3 months when they actually (if all is
well) grow faster than reference figures.  It is at about 4-6 mo that their
weight curves slow, often seem to flatten, and which used to be interpreted
as "faltering."  So its real hard to 'catch-up' a slow or poorly growing
infant during that period. And in my experience it is also real hard to
'catch up' a faltering or poorly calibrated milk supply.  Jack's use of meds
may be the only way, because I've sure hit my head against the wall after
trying everything else on those moms at 4 mo.  You can recover the supplies
of the ones who initially calibrated high enough.  But not the others.

Those babies stay kind of lean if breastfeeding continues.  I guess its not
a problem if they are otherwise healthy.  There is some data from a study I
quoted last Spring from Pediatrics on children recovering from
malnourishment which states that there is no advantage to such children from
just stuffing them with formula or high fat foods.  That doesn't seem to
improve lean body mass or muscle -- just adds fat.  That study states that
breastmilk (calories and nutrient levels) are the standard which should be
followed, even with kids recovering from malnutrition.

The truth is, we still don't know a whole lot about these mechanisms in
humans.  It is a dyadic relationship with maternal
hormonal/physical/emotional factors in interplay with the same issues in the
infant.

Barbara

Barbara Wilson-Clay, BS, IBCLC
Private Practice, Austin, Texas
Owner, Lactnews On-Line Conference Page
http://moontower.com/bwc/lactnews.html