Uterine alterations in women undergoing routine hysteroscopy before in vitro fertilization: high prevalence of unsuspected lesions

OBJECTIVE: The aim of this study was to verify the prevalence of uterine cavity abnormalities diagnosed by routine office hysteroscopy in women preparing to IVF. METHODS: We carried out a retrospective cross-sectional study of 1141 consecutive women who underwent outpatient hysteroscopy before IVF at a tertiary academic center. Of these, 961 participants had a normal transvaginal sonography (TVS) of the uterine cavity. The prevalence of hysteroscopic alterations in successive age strata was submitted to Mantel-Haenzsel Chi-square test for linear trend. The diagnostic accuracy of TVS using hysteroscopy as reference was assessed by calculating the sensitivity, specificity, positive and negative likelihood ratios. RESULTS: Hysteroscopic alterations were present in 265/961 of patients with a negative TVS (prevalence 27.6%, 95% confidence interval [CI] 24.8%-30.5%). The prevalence of unsuspected submucous leiomyoma was higher among older women (p=0.005, chi-square test for linear trend) and reached 7.2% (95% CI 3.5%-14.1%) after 40 years. The sensitivity of TVS ranged from 8% (95% CI 2%-20%) for uterine synechiae to 41% (95% CI 28%-56%) for submucous leiomyoma, resulting in low likelihood ratios for negative TVS results. CONCLUSIONS: These findings suggest a high prevalence of unsuspected alterations found by routine hysteroscopy before IVF, an age-dependent increase in the frequency of submucous leiomyoma and a low diagnostic sensitivity of TVS to detect intracavitary lesions.