Mastitis may occur any time, even in a woman who has never been pregnant. It is unusual, but occurs. It is not rare in babies when they have the breasts in the first few weeks of life. Indeed, I have seen a number of breast abscesses in newborns. I think pumping would not be such a good idea in this situation. Breasts are not supposed to be "emptied" during pregnancy. I can't think of another reason. Just gut feeling. Jack Newman, MD, FRCPC