Introduction

Excessive menstrual loss, or menorrhagia, is a significant healthcare problem in the developed world (box 1). In the United Kingdom, 5% of women of reproductive age will seek help for this symptom annually1; by the end of reproductive life the risk of hysterectomy (primarily for menstrual disorders) is 20%.2 This is also the situation in New Zealand.3 Objectively, menorrhagia is defined as a menstrual loss of 80 ml per month. Population studies have shown that this amount of loss is present in 10% of the population4 yet nearly a third of all women consider their menstruation to be excessive.5 This symptom thus creates a significant workload for health services.

In clinical medicine the paradigm of evidence based medicine currently holds sway. Evidence based medicine implies not only the application of effective treatments but their rational use within a rational overall management framework. In the management of excessive menstrual loss there is good evidence that many doctors do not necessarily prescribe the most effective treatments. In the United Kingdom, for example, more than a third of general practitioners prescribe norethisterone—arguably the least effective option—as first line treatment, whereas only 1 in 20 prescribe tranexamic acid—probably the most effective first line treatment.6 The problem is not confined to primary care. In New Zealand, where the use of tranexamic acid is restricted to secondary care, 50% of gynaecologists still use luteal phase progestogens, and less than 10% use tranexamic acid.7