Current guidelines suggest endometrial biopsy in women ³40 years old with abnormal uterine bleeding (AUB) as they are at greater risk of endometrial hyperplasia (EH) or cancer (EC). In women under 40 years old, there are no clear recommendations regarding endometrial biopsy. This should be carefully considered in younger women due to the associated risks that may affect fertility. We aim to study the profile of younger women with EH/EC in our population, to optimise endometrial biopsy in these high-risk patients.
This is an observational retrospective study that included women under 40 years old with AUB (according to the International Federation of Gynaecology and Obstetrics definition) who had endometrial biopsy in KK Women’s and Children’s Hospital Singapore in 2020. Institutional review board approval was not required for this study. Women with persistent intermenstrual bleeding > 3months or postcoital bleeding were also included. Women who had endometrial sampling on a known background of EH were excluded. Data on patient characteristics, ultrasound findings, histology and treatment were collected. Odds ratio (OR) for EH/EC as a measure of relative risk were computed.
In 2020, 128 women under 40 years old underwent endometrial biopsy for AUB. The median age was 34 years old. 40.6% were nulliparous, 21.1% had polycystic ovarian syndrome, 5.5% had diabetes mellitus, and 49.2% had a BMI > 30. The median endometrial thickness was 10mm and 18.3% had cystic spaces reported on ultrasound. Majority of histology were benign (79.0%). 13.3% had EH without atypia, 2.3% had EH with atypia, and 1.6% had EC. 75% of women with EH were treated with oral progestogen and 10% had Mirena inserted. Nulliparity (OR 6.53, 95% confidence interval (CI) 1.96-21.78) and cystic spaces (OR 7.20, 95% CI 1.87-27.64) were associated with an increased likelihood of EH/EC in these women.
The risk of EH/EC in women <40 years old is low. Endometrial biopsy should be carefully considered in younger women with AUB, and reserved for those with risk factors.