title: The effect of the levonorgestrel-releasing intrauterine system and the copper intrauterine device on subendometrial microvascularization and uterine artery blood flow.
abstract: OBJECTIVE
  To evaluate the effect of the levonorgestrel intrauterine system (LNG-IUS) and TCU 380A on the subendometrial vascularization and the uterine artery blood flow during the midluteal phase.
  
  
  METHODS
  Prospective clinical trial.
  
  
  METHODS
  Teaching hospital.
  
  
  METHODS
  The trial included 27 patients who received the LNG-IUS compared with 25 patients who received the TCU 380A.
  
  
  METHODS
  The subendometrial blood flow was evaluated using power Doppler analysis, uterine artery pulsatility index (PI), and resistance index (RI) just before inserting the intrauterine device in the midluteal phase and 3 months after.
  
  
  METHODS
  Power Doppler analysis, PI, RI, and endometrial thickness.
  
  
  RESULTS
  There were no significant differences in subendometrial vascularization between the groups. Pulsatility index and RI variability (before and after) increased and endometrial thickness reduced in LNG-IUS users. We used the multiple logistic regression model to examine the potential confounding bias (age and parity). The LNG-IUS was independently associated with increased PI.
  
  
  CONCLUSIONS
  No subendometrial microvascularization difference was found between the groups. It is the first direct evidence that LNG-IUS reduced uterine artery blood flow, even after controlling for age and parity.
authors.affiliation: Faculdade de Medicina, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Brazil. sabino@via-rs.ne
authors.forename: Mirela Foresti
authors.initials: MF
authors.lastname: Jiménez
authors.forename: Elisangela
authors.initials: E
authors.lastname: Arbo
authors.forename: Daniela
authors.initials: D
authors.lastname: Vetori
authors.forename: Fernando Monteiro
authors.initials: FM
authors.lastname: de Freitas
authors.forename: João Sabino Lahorgue
authors.initials: JS
authors.lastname: Cunha-Filho
mesh_terms: D000328:Adult; D000367:Age Factors; D001158:Arteries / Q000000981:diagnostic imaging / Q000187:drug effects; D003271:Contraceptive Agents, Female / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007435:Intrauterine Devices, Copper; D007436:Intrauterine Devices, Medicated; D016912:Levonorgestrel / Q000008:administration & dosage*; D016015:Logistic Models; D008183:Luteal Phase; D055806:Microvessels / Q000000981:diagnostic imaging / Q000187:drug effects; D016017:Odds Ratio; D010298:Parity; D011247:Pregnancy; D011446:Prospective Studies; D012039:Regional Blood Flow / Q000187:drug effects; D018615:Ultrasonography, Doppler, Color; D018617:Ultrasonography, Doppler, Pulsed; D014599:Uterus / Q000098:blood supply*
chemical_list: D003271:Contraceptive Agents, Female; D016912:Levonorgestrel