Menorrhagia is a common presentation in primary care. The gynaecological literature defines menorrhagia, as the loss of 80 ml or more of blood per period and guidelines for treatment are based on this definition. There is extensive evidence that the majority of women who complain of heavy bleeding do not fit the medical definition. We interviewed women presenting with menorrhagia to explore their perceptions and their initial interaction with the medical profession. A distinct illness model emerged. Women had a precise understanding of their complaint, so that a change in her cycle was indicative of a problem to many women, without reference to outside criteria. Women attached particular importance to how they felt and to their ability to function and they rejected the medical emphasis on blood loss evaluation. Many women were dissatisfied with the consultation and experienced doctors as being dismissive of their problem. They were seeking an explanation for why their periods had changed and had concerns that related to their understanding of menstrual bleeding. Interviewees were unsure whether period problems could be described as illness, and what range of disturbance was normal. It is suggested that the disease model of menorrhagia is not relevant to the majority of women with this complaint. It is proposed that the disease model be replaced with illness models.