title: Fetomaternal hemorrhage in relation to chorionic villus sampling revisited.
abstract: OBJECTIVE
  To investigate whether chorionic villus sampling (CVS) results in a proportional increase of alpha-fetoprotein (AFP) and fetal red cells in maternal blood.
  
  
  METHODS
  Blood samples were collected before and after CVS. The AFP concentration was measured and supervised automated microscopy of Kleihauer-Betke slides was applied to quantify fetal red cells.
  
  
  RESULTS
  AFP analysis was performed in 53 paired samples and automated microscopic scanning in 59 paired samples. Median AFP concentrations before and after CVS were 12.0 microg/L (range 6.4-36.4) and 18.7 microg/L (range 8.2-668.9), respectively, indicating a significant increase (p < 0.0001). Median numbers of fetal red cells detected before and after CVS were 0 (range 0-36) and 0 (range 0-31), respectively. No significant increase of fetal cells was observed (p = 0.72). The delta (Delta) fetal red cells and the Delta AFP correlated poorly (rho = -0.22, p = 0.11). The amount of villi correlated moderately with the Delta AFP (rho = 0.32, p = 0.02) and did not correlate with the Delta fetal red cells (rho = -0.11, p = 0.43).
  
  
  CONCLUSIONS
  Although the AFP concentration after CVS increased, no increase of fetal red cells was detected. These findings suggest that CVS results in a leakage of proteins due to placental tissue damage, rather than increased trafficking of fetal cells.
authors.affiliation: Department of Obstetrics, Leiden University Medical Center, Leiden, The Netherlands. d.m.v.pelikan@lumc.nl
authors.forename: Denise M
authors.initials: DM
authors.lastname: Pelikan
authors.forename: Humphrey H
authors.initials: HH
authors.lastname: Kanhai
authors.forename: Godelieve M
authors.initials: GM
authors.lastname: De Groot-Swings
authors.forename: Wilma E
authors.initials: WE
authors.lastname: Mesker
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Tanke
authors.forename: Sicco A
authors.initials: SA
authors.lastname: Scherjon
mesh_terms: D000328:Adult; D015193:Chorionic Villi Sampling / Q000009:adverse effects*; D004912:Erythrocytes; D005260:Female; D005331:Fetomaternal Transfusion / Q000209:etiology*; D006801:Humans; D008875:Middle Aged; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011296:Prenatal Diagnosis / Q000009:adverse effects*; D000509:alpha-Fetoproteins / Q000378:metabolism*
chemical_list: D000509:alpha-Fetoproteins