I've asked this on other lists, but no one seems to know.  Does anyone
know if the studies that show there is *no* protective effect took into
consideration whether the women supplemented  with water or ABM, early
intro. of solids, rigid scheduling, etc?  Since one of the numerous
theories about breast cancer is tied in with how many times a woman has
her period (sorry I can't think of the precise hormonal description),
and the protective effect of BF may be due to suppressed ovulation, it
would seem the researchers should have looked at this variable.  With
the early intro of solids (my MIL who did nurse her 2 boys in the 60s
gave cereal at 2 weeks on drs. orders; my mother nursed us on a schedule
and she resumed her period early), etc. my uneducated guess is that many
of the women in these studies did not experience a lack of periods, and
therefore, that alleged protective factor did not exist.

Melissa Kirsch (whose MIL just found  her breast cancer has spread to her
liver).