Esther, I contacted a pal who is nomail at the moment and relayed your posting on mother who had gas build-up with diarrhea everytime she breastfeeds. My colleague replied to me: <My guess is - oxytocin stimulates the uterus to contract in the early postnatal weeks - uterus closely related to bowel - consider the fact that many women experience diarrhoea at the onset of labour - coupled with her tendency to loose bowel motions... Would be interested to hear if effect continued with pumping... If I'm right, the problem should start to get better within a few weeks...unless it's all complicated by stress - or some hidden/emerging pathology such as irritable bowel syndrome...> kind regards, Helen M. Woodman, NCT Brfd Counsellor, UK