There was a fabulous poster presentation at the ILCA conference a few years ago that identified Y chromosomes in the ducts of mothers breasts who had just breastfed their sons. They used FISH (florescent in-situ hybridization) a very sensitive molecular genetic technique. So we have our first proof that baby's saliva ascends mother's ducts during or after breastfeeding. That could easily provide information to the breast about the infants maturational and immunological challenges! Congrats to all the new IBCLC's! Catherine Watson Genna, IBCLC NYC *********************************************** Archives: http://community.lsoft.com/archives/LACTNET.html To reach list owners: [log in to unmask] Mail all list management commands to: [log in to unmask] COMMANDS: 1. To temporarily stop your subscription write in the body of an email: set lactnet nomail 2. To start it again: set lactnet mail 3. To unsubscribe: unsubscribe lactnet 4. To get a comprehensive list of rules and directions: get lactnet welcome