Small cysts could be involved.  I also wonder if the over zealous heat and
massage that some of these moms do adds to the problem instead of relieving
it.
I worked with a mom who had repeated multiple plug ducts.  They were usually
in just one breast but occasionally in the other.  After persistent massaging
and nursings they would go down but then return in a few days.  At times they
would increase in size and she was treated at least twice for mastitis (this
was not my diagnosis but the physician did not know what to do for this mom).
 On one of my exams of her breast when the ducts were fairly soft I found
small clusters of 'pea' size lumps.  I had her get an ultrasound and dx of
fibrocystic tissue.  I had her cut out the heat and decrease the massaging,
cont the nursings and Lethicin.  The plug ducts decreased in occurances.
If a mom is over zealous of her massaging, the sensitive breast tissue can
then pull in lymph fluid and then swell and diminish drainage.  What about
sending her to a lymphatic massage treatment?  This was discussed at the
Scottsdale ILCA conf.
Good luck.
Ann Perry RN, IBCLC
Boston, MA

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