It is true that you don't want the mother's Rh- blood to enter the Rh+ baby's bloodstream (and no, the two blood systems usually don't mix across the placenta, they merely come close together and exchange gases (oxygen and carbon dioxide) and nutrients/wastes. But cracked and bleeding nipples, while sore and painful, are not a contraindication to nursing because the blood will go into the baby's stomach and be digested, not into the baby's bloodstream. The mother might have anti-Rh+ antibodies in her blood which would attack the baby's Rh+ red blood cells if the baby were to get maternal blood directly into the baby's bloodstream. But the mother's anti-Rh+ antibodies will be digested in the baby's stomach, not absorbed intact into the bloodstream, and she probably has very low levels anyway because of the Rhogam shots. Tell her not to worry! ---------------------------------------------------------------------------- ------- Katherine A. Dettwyler, Ph.D. email: [log in to unmask] Anthropology Department phone: (409) 845-5256 Texas A&M University fax: (409) 845-4070 College Station, TX 77843-4352