Hysteroscopic findings in postmenopausal patients using tibolone

Objective To investigate the cause of uterine bleeding in tibolone users who were referred to an endoscopy unit.

Design Hysteroscopy followed by endometrial biopsy was carried out in all patients. The endometrial echo was measured by transvaginal sonography prior to hysteroscopy and compared with hysteroscopic findings.

Results Endometrial polyps were the pathological lesions most frequently diagnosed by hysteroscopy in tibolone users. However, their diagnosis was missed by blind endometrial biopsy in all cases. The surrounding endometrium was always atrophic even when a polyp was present in the uterine cavity. There was one case of endometrial carcinoma which occurred in association with a polyp.

Conclusion Tibolone does not exert any stimulatory effect on the normal endometrium. However, intrauterine lesions such as polyps can grow in response to this treatment. The presence of polyps is associated with abnormal uterine bleeding in these patients.