The mother of a  4 month old has nursed uneventfully except for occasional
plugs, which begin as a lump higher in the breast (either one), work their
way down, and resolve.

Recently she had a much larger hard area - hand-sized - that took longer to
resolve and seems to have left a lump, marble-sized, under her areola.
She's not sure whether that hard spot has always been there, in fact, but
she noticed a stain on her bra, and on exploring and squeezing the lump,
found that she could express straw-colored, watery, slightly salty fluid
from a "montgomery gland" on her areola.  She can express fluid from that
spot without expressing milk from her nipple, and seems to be able to
express unlimited quantities.  The lump isn't sore unless she goofs around
with it too long.

Her baby has begun showing a preference for the "normal" breast within the
past month, though not strongly.  (For instance, when she wants to settle
him fast in public, she uses his preferred side.)

Whaddya think?

Diane Wiessinger, MS, IBCLC, LLLL  Ithaca, NY