RESUMEN
OBJECTIVE: To compare the effects of the levonorgestrel-intrauterine system (LNG-IUS) and depot-medroxyprogesterone acetate (DMPA) on subendometrial vascularisation and uterine artery blood flow. STUDY DESIGN: The trial compared 25 patients wearing a LNG-IUS and 25 patients receiving DMPA. The subendometrial blood flow was evaluated using power Doppler analysis; the pulsatility index (PI) and resistance index (RI) in the uterine artery and spiral arteries were evaluated with spectral Doppler. RESULTS: The PI and RI of the uterine artery and endometrial thickness did not differ significantly between the two groups. The subendometrial vascularisation was lower and the PI in the spiral arteries was higher in DMPA-users. CONCLUSION: In spite of a similar prevalence of bleeding disturbances, the effects of DMPA and the LNG-IUS on the subendometrial microvascularisation differ.