Primary and myoma-associated menorrhagia: role of prostaglandins and effects of ibuprofen

Summary. The release of 6-keto-prostaglandin F_1α(6-keto-PGF_1α), a metabolite of prostacyclin (PGI₂) and thromboxane B2 (TxB2), a metabolite of thromboxane A2 (TxA2), was estimated in endometrial biopsies taken from 12 menorrhagic and 12 healthy women during the luteal phase of the cycle. The releases of 6-keto-PGF_1α and TxB2 were normal, but the ratio TxB2/6-keto-PGF_1α was inversely related to menstrual blood loss in women with measured menstrual blood loss exceeding 70 ml. In the second part of the study, 24 women with excessive menstrual bleeding (13 with primary menorrhagia, 10 with uterine fibro-myomas, one with haemostatic factor VIII deficiency) were treated at random with ibuprofen (600mg/day and 1200mg/day) and with a placebo. Ibuprofen 1200 mg/day reduced (P<0.01) median blood loss from 146 ml (range 71–374 ml) to 110 ml (30–288 ml) in primary menorrhagia but had no effect on blood loss in women with uterine fibroids and factor VIII deficiency. Blood loss was normal in six women and was not affected by ibuprofen. Thus, our data suggest that there is a PGI₂ dominance in the endometrium of patients with menorrhagia. In addition, primary, but neither fibromyoma nor coagulation defect-associated menorrhagia, can be treated by ibuprofen.