title: Endothelial function in women using levonorgestrel-releasing intrauterine system (LNG-IUS).
abstract: BACKGROUND
  Oral levonorgestrel has been linked to increased cardiovascular risk, but currently, no information is available on the effect of the levonorgestrel-releasing intrauterine system (LNG-IUS) on endothelial dysfunction. The objective of this study was to assess endothelial function in LNG-IUS users.
  
  
  METHODS
  Sixty women underwent insertion of either an LNG-IUS (n=30) as study group or Copper-T intrauterine contraceptive device (TCu 380A intrauterine device) as control group (n=30). In the midluteal phase of menstrual cycle, endothelium-dependent flow-mediated dilatation (FMD) and endothelium-independent dilatation of brachial artery were studied before and after 3, 6 and 12 months of device insertion. We also assessed the correlation of FMD and serum concentrations of estradiol (E2), progesterone (P) and LNG.
  
  
  RESULTS
  With LNG-IUS, there was a nonsignificant decrease in mean FMD of brachial artery (p>.05) compared with the control group at different time points of the study. Before LNG-IUS, reactive hyperemia caused an 8.3%±1.3% increase in brachial artery diameter compared with 7.1%±1.1%, 7.4%±0.9% and 7.5%±0.9% after 3, 6 and 12 months of LNG-IUS (p>.05). The mean±SD LNG plasma levels at 3, 6 and 12 months of LNG-IUS application were 228±87, 204±94 and 191±79 pg/mL, respectively. E2 levels were comparable in women of both studied groups. Mean P levels were significantly lower after LNG-IUS insertion compared with before device insertion and with the control group (p<.05) at all study visits. No correlation was found between LNG levels and FMD.
  
  
  CONCLUSIONS
  A nonsignificant change detected in endothelial function in LNG-IUS indicates that it has no increased cardiovascular risk.
authors: Department of Obstetrics and Gynecology, Zagazlg University, 44519 Zagazlg, Egypt. mfselim@hotmail.com
authors: Mohamed Fouad
authors: MF
authors: Selim
authors: Adnan Fathey
authors: AF
authors: Hussein
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D003271:Contraceptive Agents, Female / Q000008:administration & dosage / Q000009:adverse effects*; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D007436:Intrauterine Devices, Medicated / Q000009:adverse effects*; D016912:Levonorgestrel / Q000008:administration & dosage / Q000009:adverse effects*; D011247:Pregnancy; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D003271:Contraceptive Agents, Female; D016912:Levonorgestrel