Unscheduled bleeding on HRT - do we always need to investigate for endometrial pathology?


  • Ying Yiing Lou Department of Obstetrics and Gynecology, Watford General Hospital, Vicarage Road, Watford, WD18 0HB, UK
  • Jeyanthan Kannappar Department of Obstetrics and Gynecology, Barnet General Hospital, Wellhouse Lane, Barnet, EN5 3DJ, UK
  • Sahathevan Sathiyathasan Department of Obstetrics and Gynecology, Princess Royal University Hospital, Farnborough Common, Orpington, BR6 8ND, UK




Breakthrough bleeding, Hormone replacement therapy, Menopause, Unscheduled bleeding


Hormone replacement therapy (HRT) is the most effective method for relieving the effects of hypoestrogenism following menopause. Despite the benefit of the HRT, unscheduled/breakthrough bleeding decreases patients’ compliance with long-term use. The underlying mechanisms for this unpredictable breakthrough bleeding are less well understood. In the event of unscheduled bleeding, investigation may be necessary according to local protocol. Whilst the incidence of underlying benign pathology may be quite high, the likelihood of malignancy is low and unless there is particular clinical concern, these women do not need fast track referral which should be reserved for women with true postmenopausal bleeding.


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