The Association Between Adenomyotic Abnormal Bleeding and Prevalence of Bacterial Vaginosis

Background: Bacterial vaginosis (BV) is one of the most common vaginal conditions and is associated with significant obstetric and gynecological risks. Previous studies have demonstrated an association between menses and the vaginal dysbiosis underlying the development of BV. Given this association, we hypothesized that increased vaginal bleeding, such as abnormal uterine bleeding (AUB) caused by adenomyosis, might increase the risk of developing BV. Objective: This study assesses whether AUB in patients with adenomyosis was associated with BV diagnoses. Methods: We performed a retrospective study of 372 patients diagnosed with adenomyosis between 2016 and 2020 at a tertiary care center. Characteristics of patients who developed BV within 3 years of adenomyosis diagnosis were compared to patients without subsequent BV diagnoses. Results: The prevalence of BV in patients diagnosed with adenomyosis between 2016 and 2020 was 19.4%. Patients who developed BV following their diagnosis of adenomyosis had higher rates of menorrhagia than those who did not develop BV (p < 0.01). While patients with BV were primarily diagnosed with adenomyosis by radiological findings, patients without BV were mostly diagnosed with adenomyosis by post-hysterectomy histopathologic evaluation. Treatment of adenomyosis-related symptoms was significantly different between the two study groups. There was also a positive association between the prevalence of menorrhagia and the number of BV episodes, demonstrating a relationship between AUB and BV. Conclusions: This study provides evidence for an association between the menorrhagia caused by adenomyosis and a diagnosis of BV. Based on these findings, prospective studies are needed to assess the contribution of abnormal uterine bleeding pathologies to the development of BV.