Introduction/Background Unscheduled bleeding, including post menopausal bleeding, is a potentially concerning but common presenting complaint to gynaecology 2 week wait (2WW) clinics. There has been an increase in patients presenting with unscheduled bleeding largely due to an increase in use of hormone replacement therapy (HRT) in recent years. Transvaginal ultrasounds (TVUS) measuring endometrial thickness (ET), endometrial biopsies and hysteroscopies are pivotal diagnostic tools to detect abnormal uterine pathology. The aim of this study is to determine a safe cut off for ET when investigating unscheduled bleeding in patients on HRT.

Methodology We looked at patients who attended the gynaecology 2WW clinic from January to April 2022 at a busy district hospital. We explored the investigations these patients underwent and compared the outcomes patients on HRT to those not on HRT.

Results 471 patients presented to the 2WW with an average age of 57 and unscheduled bleeding was by far the most common presenting complaint. 30% of perimenopausal/menopausal patients were on HRT. 67 of these patients had a TVUS, 51 of those with an ET of >4mm underwent pipelle biopsies and/or hysteroscopies; all with benign results. Compared to the 70% of perimenopausal/menopausal patients not on HRT, 62 patients had a TVUS showing an ET>4mm; 11 of these patients were found to have either dysplasia or cancerous cells of endometrium. All patients with an ET <4mm in both groups had benign results.

Conclusion Our results suggest that patients presenting with unscheduled bleeding on HRT are much more likely to have unscheduled bleeding because of their HRT rather than underlying endometrial cancer. We propose a different management approach to patients on HRT by using a higher ET cut off and even management in primary care rather than referral to 2WW. This would improve efficiency of resources and decrease unnecessary investigations, thereby improving patient outcomes.

Disclosures Nil.