Paul, I found two nice ref. for you from some Brazilian researchers.  I
wonder are they part of the Groupo which is also on-line?

Vitolo,M. et al.  Colostrum Composition in Adolescent Mothers, J Am College
of Nurt, 1993; 12(5):547-550.

Brasil,A. et al. Fat and Protein Composition of Mature Milk in Adolescents,
J Adol Health, 1991;12:365-371.

Both undertook chemical analysis to investigate the influence of adolescence
on milk composition.  The conclusion of both studies was that there is
functional maturity of the adolescent breast, and "breastfeeding by
adolescent mothers of any socioeconomic level is a indicated as that by
adult mothers." (Vitolo, 1993.)

Hope this helps,
Barbara Wilson-Clay, BSE, IBCLC
priv. pract. Austin, Tx
Owner LAVTNEWS On-Line (the Conference Page)
http://moontower.com/bwc/lactnews.html