BACKGROUND: Mastitis is a common problem for breastfeeding women in the postpartum period. METHODS: Ninety-four breastfeeding women participating in a case control study of mastitis provided a free text comment about their experience of mastitis. Women were recruited from the emergency department, wards or breastfeeding clinics of the Mercy Hospital for Women and the Royal Women's Hospital, Melbourne, in 2002-2004. RESULTS: The main themes which emerged from the free text comments were: acute physical illness; negative emotions; life disrupted; to continue breastfeeding or not? A minor theme was 'support for mastitis research'. DISCUSSION: Women with mastitis often experience a rapid onset physical illness accompanied by strong negative feelings, which leads some women to consider stopping breastfeeding while others are determined to persevere. General practitioners need to provide emotional support for women with mastitis and acknowledge that breastfeeding may be difficult for new mothers.