Laurie,
Several months ago the "4.2 yrs" number was quoted, and then challenged,
in the misc.kids.health newsgroup. I took it upon myself to track this
one down, and this is what I found:

First, it is Ruth Lawrence who quotes this statistic and seems to be the
source who popularized it. The source is not referenced in her book, so I
called her office directly to inquire. According to them, she obtained
this number from a study done by Ross Labs many years ago (Breastfeeding
Compendium). I then wrote to Ross, who informed me that the study was no
longer available, and who could provide no further information as to how
it was done. I was curious as to how they conducted the study, or how
whoever did it conducted it, but I came to a deadend. Not very
satisfying, but that was where my inquiry led. I do have a copy of the
letter from Ross if anyone is interested.
-Lisa

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Lisa A. Marasco, IBCLC                                /  [log in to unmask]
International Board Certified Lactation Consultant    /  [log in to unmask]

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