Atrophic endometrium in postmenopausal women referred to diagnostic hysteroscopy: a study to avoid unnecessary examinations.

Any diagnostic workup should be based on appropriateness criteria. Diagnostic hysteroscopy is a procedure widely used in endometrial pathology. Its high outpatient feasibility frequently leads to misuse. However, it can cause discomfort and, albeit rarely, complications. The present study aimed to provide an estimate of unnecessary examinations based on variables associated with atrophic endometrium in postmenopausal women referred to diagnostic hysteroscopy. One-hundred and sixty-six postmenopausal women undergoing hysteroscopy were retrospectively analyzed. All included women had a final histological reference standard. The sample was divided into women with atrophic endometrium vs. women with endocavitary lesions (benign/premalignant/malignant). Univariate and multivariate analysis was performed to assess those patient characteristics associated with atrophic endometrium. Furthermore, based on the likelihood ratios, a post-test probability analysis was performed to provide an estimate of atrophy according to the presence of specific variables. Sixty-one postmenopausal women (36.7%) undergoing diagnostic hysteroscopy showed atrophic endometrium at final histology. Multivariate analysis showed that the independent variables associated with atrophy were the absence of abnormal uterine bleeding [Odds Ratio (OR)=6.43, Confidence Intervals (CI) 2.087 to 19.822], and endometrial thickness (criterion < 7 mm) (OR=0.417, CI 0.300 to 0.578). In women showing both variables associated with negative endometrial outcome, post-test probability analysis resulted in an atrophic endometrium rate of 89.13%, from a pre-test probability of 36.7%. About 90% of asymptomatic postmenopausal women with endometrial thickness <7 mm resulted in an atrophic endometrium at hysteroscopy. Every gynecologist should know and consider these data before referring such women to further examinations. In these cases, diagnostic hysteroscopy is not cost-effective leading to a high number of false positives.