title: Chorionic villus sampling at 11 to 13 weeks of gestation and hypertensive disorders in pregnancy.
abstract: OBJECTIVE
  To estimate the potential association of chorionic villus sampling (CVS) with subsequent development of hypertensive disorders of pregnancy and to evaluate whether any such potential association remains significant after adjusting for maternal characteristics and components of first-trimester screening.
  
  
  METHODS
  We included live singleton pregnancies at 11 0/7 to 13 6/7 weeks surviving to beyond 23 weeks of gestation with available measurements of free beta-hCG and pregnancy-associated plasma protein A. We excluded pregnancies resulting in miscarriage or termination before 24 weeks of gestation, women with no known pregnancy outcome, and women who had an amniocentesis. Multiple logistic regression analysis was used to determine whether CVS, in addition to factors in the maternal history and characteristics, made a significant contribution to the development of preeclampsia and gestational hypertension.
  
  
  RESULTS
  Included in the study were 31,138 women, of whom 697 (2.2%) had preeclampsia subsequently develop, and 857 (2.8%) had gestational hypertension develop. In 2,278 (7.3%) individuals, a CVS was performed. Multiple logistic regression analysis demonstrated that although there were significant contributions from maternal factors and serum biochemistry, a CVS in the first trimester did not contribute significantly to subsequent development of early preeclampsia (P=.677), late preeclampsia (P=.535), or gestational hypertension (P=.848).
  
  
  CONCLUSIONS
  There is no association between performing a CVS in the first trimester and subsequent development of hypertensive disorders of pregnancy.
  
  
  METHODS
  II.
authors.affiliation: From the Department of Fetal Medicine, Institute for Women's Health, University College Hospital, and Department of Fetal Medicine, Kings College Hospital, London, United Kingdom.
authors.forename: Asma
authors.initials: A
authors.lastname: Khalil
authors.forename: Ranjit
authors.initials: R
authors.lastname: Akolekar
authors.forename: Pranav
authors.initials: P
authors.lastname: Pandya
authors.forename: Argyro
authors.initials: A
authors.lastname: Syngelaki
authors.forename: Kypros
authors.initials: K
authors.lastname: Nicolaides
mesh_terms: D000328:Adult; D015193:Chorionic Villi Sampling / Q000009:adverse effects*; D005260:Female; D006801:Humans; D046110:Hypertension, Pregnancy-Induced / Q000209:etiology*; D011247:Pregnancy; D011261:Pregnancy Trimester, First