Mardrey Swenson wants a reference on this - please refer to Neville & Neifert's book "Lactation" and Infant Feeding, the Physiological Basis. Newer research is coming from Peter Hartmann's work in Australia. It appears the inhibitors are (1) peptide fragments, (2) possibly medium-chain fatty acids, and (3) physical pressure. Maybe more. Still the same prinicple - supply and demand (demand dictates supply) or more accurately "use it or lose it." Linda Smith, private practice, Dayton OH.