Systemic causes of heavy menstrual bleeding

Heavy menstrual bleeding (HMB) is a common problem in fertile women. In addition to local factors, such as a polyp or a uterine fibroid, systemic causes may lead to HMB. These systemic causes are discussed in this thesis. For years, women with HMB were tested underlying thyroid disorder, but our research shows that this is not necessary or helpful. We found that the prevalence of a thyroid disorder in these women is the same as in the general population. Another cause of HMB is a factor XI deficiency (coagulation disorder). We have shown that women with HMB have relatively lower factor XI levels in comparison with the control group, which may contribute to their heavy menstrual bleeding. Unexpectedly we found a decreased fibrinolysis (breakdown of blood clots) in women with HMB, while an increased fibrinolysis is thought to contribute to HMB. We have also examined whether a defect in the factor 11 gene might be a cause for HMB, but this is not clearly the case. From our systemic literature search we have demonstrated that women with factor XI deficiency are at greater risk of bleeding after curettage, childbirth or surgery and that they also have an increased risk of heavy menstrual bleeding.
To test all women with heavy menstrual bleeding for underlying coagulation disorders involves costs. That is why we have developed a simple screening tool, consisting of 5 items, to screen whether it is necessary to test these women for underlying bleeding disorders.