Factors Associated with Insufficient Endometrial Sampling in Postmenopausal Women

Aim:To assess the risk factors associated with high rate of insufficient endometrial sampling on endometrial biopsy in postmenopausal women.Methods:Data were retrieved from the records of 522 consecutive patients who underwent endometrial sampling. Logistic regression analyses were performed to determine various factors associated with scanty endometrial biopsy. The exclusion criteria included patient refusal, uncertain menopausal status, cervical carcinoma detected after sampling and unavailable records.Results:The sample was insufficient for a definitive diagnosis in 143 (25.9%) patients. Out of these, 53 cases were investigated with invasive procedures. Further histopathological examination revealed that five (9.4%) patients had uterine malignancy. Based on the multivariate analysis, time since the onset of menopause [Odds ratio (OR)=1.044, 95% confidence interval (CI)=1.000-1.090, p=0.049] was significantly associated with insufficient endometrial biopsy in cases with a endometrial thickness of >12 mm on ultrasonography (OR=0.624, 95% CI=0.472-0.824, p=0.001). The use of dilation and curettage technique (OR=0.662, 95% CI=0.522-0.841, p=0.001) decreased the risk of insufficient sampling on endometrial biopsy.Conclusion:Time since the onset of menopause and the thickness of endometrium were significant independent factors associated with insufficient sample. Using Karman cannula for endometrial aspiration may not be a reliable method in the evaluation of postmenopausal women. An insufficient endometrial sample does not rule out endometrial carcinoma, therefore, a further histopathological examination is recommended.