Evidence that progesterone alone will decrease the milk supply FOR SOME MOTHERS
is abundant in Australia: at every course I run there are NMAA counsellors
or Maternal and Child Health Nurses, the people who see most breastfeeding
mothers at every stage of lactation, who have clearly convincing case
histories. Fact is, MOST mothers can get away with the mini-pill and not be
affected; some have irritable babies but no drop in supply, and some have
irritable babies because of a genuine and remediable drop in supply.  It
would take very large studies indeed to spot the small numbers affected,
and most studies to date have been too small to do so. I remember a key
study of about 100 women which came to the conclusion that there was no
effect on breastmilk composition or volume. I knew the researcher and said,
Hey, but we get babies described all the time as fussy with mother on the
mini-pill, often within 24-48 hours of her beginning it, and wonderful when
she drops it, as so many do because of whet they interpret as a drop in
supply. Did you see such cases? If there's no volume change, what's going
on? The reply was unnerving: "yes, we saw such babies among the 100 we
studied. But there was no volume change and none of the few constituents
measured (vit A as I recall) changed. However, it could be a direct
cerebral effect on the infant brain making the infant irritable."

I was not reassured, and ever since have strongly recommended LAM and
barrier methods, especially for mothers of young babies whose sole diet is
breastmilk. For I also read a fascinating article revealing huge
discrepancies in rates of transfer of active ingredient from plasma into
milk: something like a 13-92% range, I seem to remember. At the low end of
the absorptive spectrum there may be no effect, but at the upper end, or in
cases of extreme sensitivity to hormonal action, such things can be
significant. Given the complexity of infant brain development and the
impact of hormones, I'm naturally conservative here.

Which is not to say that I'd never recommend the mini-pill: if you must
take steroids it's the best bet we have. However, it is crucial that
mothers realise what tiny margins for error there are: most don't know that
a bout of loose stools or anything affecting gut motility and absorption
can mean no protection. I suspect that LAM prevents more pregnancies than
the mini-pill does in women under 6 months post-partum, yet the mini-pill
gets the credit and LAM is considered risky. Ha!

Maureen

Maureen Minchin, IBCLC
5 St, George's Rd., Armadale Vic 3143 Australia
tel/fax after March 1: 61.3.95094929 or 95000648