Hi Melissa -

Just happened to have a couple of studies in my desk drawer about
breastfeeding as a method of birth control

In LANCET (April 18, 1992 - Alfredo Perez, Miriam H. Labbok, & John T.
Queenan), LAM was concluded to be "a successful family planning method with
high acceptance and an efficacy of 99.5%" as an "introductory method" of
birth control, but only for the first 6 months.  The women studied were from
middle-class urban Santiago, Chile, and exclusive breastfeeding was
encouraged, although up to one supplemental feeding of not more than 60
ml/week was allowed.  Women were encouraged to maintain night feedings, and
told that when supplementation with food or menstrual flow returned, an
additional method of birth control would be required.

In LANCET (Jan 25, 1992 - Kathy I. Kennedy & Cynthia M. Visness) studied
statistics from a wide variety of countries.  They stated that with LAM, the
probablility of pregnancy was 3% at 6 months, and 6% at 12 months.  They said
good breastfeeding counselling and practices were necessary.  They also
recommend an additional birth control method when menses restarted. I'm
afraid that they state only 47 of 346 women remained free from menses after
12 months, and this was considered an end of the efficacy of LAM.

I think I remember from somewherethat actively breastfeeding mothers average
21 months between pregnancies, and mothers not breastfeeding average 14
months - but can't think of where to look to verify these figures (I have a
tendency to remember numbers, but not where they come from, sorry).

Hope this helps!

Donna L. Coe RN IBCLC
in Syracuse, NY where the (relatively) warm weather is supposed to change to
snow by tomorrow - well, that's life in the "snow belt"