From: Becky B.

I've known several moms who quit bf or started supplementing due to the
drop off of their supply following a depo shot.  I think it is probably
because isn't depo supposed to mimic pregnancy like bcps do?  I do
know that in pregnancy the milk supply turns back into colostrom
at about 2-3 months.  Maybe the same thing happens with depo only to
a lesser extent perhaps.

Becky B.