I was at the ILCA conference and the Medela pre conference.  While Dr.
Hartman's team was demonstrating the breast function during nursing and
pumping, they were describing how the ducts responded.  The ducts appear the
same near the nipple as they do farther out.  As the baby or pump stimulate
the breast and the hormones respond the ducts start to dialate and then there
is a let down.  They also described the ducts as being very sensitive to too
much pressure and if she pushed too hard with ultrasound transducer the duct
would colapes.  I asked her at the end of their presentation how the drawings
of the lactating breast came to be and she said back in the 1800's a
scientist had access to a cadavier of a lactating woman.  He removed her
breast and poured colored wax into the ducts and then made the drawings the
wax made the ducts near the nipple over fill.  What they are seeing now on
ultrasound is that the ducts can dilate at different parts of the breast, not
just behind the nipple and there are no "lactiferous sinuses" as we know
them.
This does make sense to me when looking at the anatomy of the nonpregnant
breast and they are more similiar to these new images of the lactating
breast. (Branches starting at the nipple similiar to a tree's roots just as
Jean described.)
Next, to tie this in with hand expressing and pumps; when compressing behind
the nipple where the baby's mouth would be, is to stimulate the MER because
of the hormones are being stimulated not because one can just squeezes out
milk?  Mothers should not expect to see milk the first compression with their
fingers and should be encouraged to work around the nipple until the milk
starts to eject.  Right?

This is all so fasinating to me and I do hope I am making sense in my post.
Ann Perry, RN IBCLC
Boston, MA
PS.  Re. the O'Reilly Factor post I want to correct my post to thank Lynda
for her comments not Lydia.

             ***********************************************

To temporarily stop your subscription: set lactnet nomail
To start it again: set lactnet mail (or digest)
To unsubscribe: unsubscribe lactnet
All commands go to [log in to unmask]

The LACTNET mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software together with L-Soft's LSMTP(TM)
mailer for lightning fast mail delivery. For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html