I would say that the reason there is so much differing opinion about
breastfeeding and the pill, and breastfeeding and just about anything else
is that many of the people who sound off about these issues know nothing
about breastfeeding.

First, there may be some women who prefer the pill to breastfeeding, but
there are also lots that are hopping mad when they find out the pill
decreased their milk supplies.  Whoever said that once the milk supply is
established the mother can take combo pills also doesn't know what he's
talking about.  The combo pill does not always seem to make a difference in
the milk supply, but it often does.  And I have seen it cause a significant
decrease in the milk of mothers who are nursing 5 month old babies
exclusively with no problems until the pill starts.

Jack Newman, MD, FRCPC