title: Ultrasound-guided hysteroscopy to remove a levonorgestrel intrauterine system in early pregnancy.
abstract: BACKGROUND
  Correctly placed levonorgestrel-releasing intrauterine systems (LNG-IUSs) are rarely associated with intrauterine pregnancy when pregnancy occurs. LNG-IUS retrieval, termination of pregnancy and conservative management if retracted strings prevent ready removal are the usual clinical options given to women. The conservative course raises concerns about teratogenesis related to high local progestin exposure for the developing fetus.
  
  
  METHODS
  This case report describes combined saline hysteroscopy and ultrasound to retrieve an LNG-IUS at less than 9 weeks of gestational age. A systematic review of the literature was performed to identify similar case reports by contacting the manufacturer and searching Pubmed from 1900 through November 2011 using the terms ((levonorgestrel AND intrauterine) OR mirena) AND (pregnan* OR fetal OR fetus OR teratogen*) NOT (menorrhagia OR hyperplas* OR ectopic OR malig* OR cancer).
  
  
  RESULTS
  We identified 37 cases of LNG-IUS pregnancy exposures in the absence of spontaneous expulsion or myometrial or intraperitoneal placement of LNG-IUS. Given the presence of two congenital anomalies reported in the group, the anomaly rate is 5.4%, 95% confidence interval 0% to 11.5%.
  
  
  CONCLUSIONS
  Intrauterine LNG-IUS exposure is associated with a low frequency of congenital anomalies. Combining hysteroscopy with ultrasound facilitates surgically precise LNG-IUS removal despite retracted strings.
authors.affiliation: Department of Perinatal Medicine, Mercy Hospital for Women, Heidelberg, VIC 3078, Australia. eamcca@unimelb.edu.au
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: McCarthy
authors.forename: Nisha
authors.initials: N
authors.lastname: Jagasia
authors.forename: Peter
authors.initials: P
authors.lastname: Maher
authors.forename: Miranda
authors.initials: M
authors.lastname: Robinson
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000453:epidemiology / Q000209:etiology; D000328:Adult; D003271:Contraceptive Agents, Female / Q000009:adverse effects; D005260:Female; D005865:Gestational Age; D006801:Humans; D015907:Hysteroscopy / Q000379:methods*; D007436:Intrauterine Devices, Medicated / Q000009:adverse effects; D016912:Levonorgestrel / Q000009:adverse effects; D011247:Pregnancy; D014463:Ultrasonography; D016216:Ultrasonography, Prenatal
chemical_list: D003271:Contraceptive Agents, Female; D016912:Levonorgestrel