title: Chorionic villous sampling: experience of 636 cases.
abstract: OBJECTIVE
  To describe the technical aspects and complications of chorionic villous sampling (CVS).
  
  
  METHODS
  The database of CVS procedures performed between January 2004 and August 2011 at Maharaj Nakorn Chiang Mai Hospital was assessed prospectively. Consecutive procedures during 10 to 14 gestational weeks were included into the present study. Indications, results, and complications of the CVS were extracted and analyzed.
  
  
  RESULTS
  All 636 CVS procedures were successful. Indications for CVS were fetal karyotyping, DNA analysis for severe thalassemia disease, and for both in 36.5%, 50. 6%, and 12.9%, respectively However, 3.4% had inconclusive CVS result, and the second trimester prenatal diagnosis procedures needed to be done. There were five cases (0.8%) of fetal loss in the present study. Only two cases (0.3%) that fetal loss happened within two weeks of CVS procedures. Other minor complications such as vaginal bleeding and amniotic fluid leakage were found in 0.3 to 1.3% and had no long-term effect. No case with anomaly and procedure-related infection following the procedure was seen.
  
  
  CONCLUSIONS
  CVS is a safe and reliable prenatal diagnosis procedure in the first trimester. In experienced operators, fetal loss rate was less than 1%. However a few cases will have inconclusive CVS results and may need a confirmation during the second trimester diagnostic procedures.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine Chiang Mai University, Chiang Mai, Thailand. aey_uraiwan@hotmail.com
authors.forename: Uraiwan
authors.initials: U
authors.lastname: Laksanavilai
authors.forename: Wirawit
authors.initials: W
authors.lastname: Piyamongkol
authors.forename: Supatra
authors.initials: S
authors.lastname: Sirichotiyakul
authors.forename: Fuanglada
authors.initials: F
authors.lastname: Tongprasert
authors.forename: Suchaya
authors.initials: S
authors.lastname: Leuwan
authors.forename: Kasemsri
authors.initials: K
authors.lastname: Srisupundit
mesh_terms: D000328:Adult; D015193:Chorionic Villi Sampling / Q000009:adverse effects; D005260:Female; D006801:Humans; D011247:Pregnancy; D012189:Retrospective Studies