Bckground: The main cause for discontinuation of DMPA use is irregular menstrual bleeding. The exact pathophysiological mechanisms of irregular bleeding have remained unclear. Transvaginal Doppler is a non invasive method for studying changes of blood flow which may highlight the underlying pathology in those cases with irregular uterine bleeding. The aim of the study was to quantify the uterine and subendometrial microvasculature in DMPA users with irregular bleeding pattern in comparison to DMPA users with amenorrhea .Study design: This is a case control study. Forty users of DMPA were divided into two groups: one group included 20 users with irregular uterine bleeding and the second group included 20 amenorrheic users. Pulsatility Index (PI) and resistant Index (RI) of uterine and subendometrial blood vessels were determined. Power Doppler Energy (PWE) used to qunitify the subendometrial area signal percentage. Results: There is significant reduction of PI and RI in uterine artery and subendometrial microvasculature in cases with irregular uterine bleeding. Conclusion: Irregular uterine bleeding with DMPA associated with increased perfusion of uterine and subendometrial blood vessels.
Key words: DMPA, PI, RI, subendometrial doppler