LAUSR

Study Objective To assess trends in practice pattern and racial and ethnic differences among women who underwent minimally invasive myomectomy (MIM) for benign uterine leiomyomas. Design Retrospective observational data-only cohort study. Setting A large integrated healthcare delivery organization serving over one million reproductive-aged women annually. Patients or Participants Women aged 18 or older who underwent a myomectomy for benign leiomyoma between 2009 and 2019 within Kaiser Permanente Norther California were included. Cases with hysterectomy, pregnancy-related procedures, or malignancy were excluded. Interventions N/A Measurements and Main Results Between 2009 and 2019, a total of4040 women underwent a myomectomy for benign uterine leiomyoma with an incidence rate of 0.12 (95% confidence interval [CI] 0.12-0.13) in 2009 to 0.25 (95% CI 0.24-0.25) in 2019 per 1000 women (Table 1). Over the 11-year period, the rate of MIM increased from 6.5% to 89.5% (1280% increase) with an increase in robotic myomectomy from 3.6% in 2012 to 64.6% in 2019. Unadjusted prevalence of MIM increased at a higher rate for non-Hispanic white women than others (Figure 1). Future analyses, adjusting for patient and healthcare system characteristics including fibroid weight and surgeon operating volume, will determine if racial/ethnic variations in myomectomy route persist over time. Conclusion Within an integrated healthcare delivery system, initiatives to encourage minimally invasive surgery had a substantial impact on increasing the number of MIM for all women, although white women saw the greatest increase compared to their racial and ethnic counterparts. Further research is needed to identify determinants of racial and ethnic disparities in MIM rates.