title: Elevated second-trimester maternal serum β-human chorionic gonadotropin and amniotic fluid alpha-fetoprotein as indicators of adverse obstetric outcomes in fetal Turner syndrome.
abstract: OBJECTIVE
  The objective of this study was to determine the ability of biochemical analytes to identify adverse outcomes in pregnancies with Turner syndrome.
  
  
  METHODS
  Maternal serum and amniotic fluid (AF) marker concentrations were measured in 73 singleton pregnancies with Turner syndrome (10-22 weeks of gestation). Fetal Turner syndrome was definitively established by cytogenetic analysis. Two subgroups, fetuses with hydrops fetalis versus fetuses with cystic hygroma, were compared. Receiver operating characteristic curves and relative risk were established for a cut-off multiples of the median ≥3.5 for β-subunit of human chorionic gonadotropin (hCG) or AF alpha-fetoprotein (AFP).
  
  
  RESULTS
  Forty-nine (67%) of 73 pregnant women had an abnormal maternal serum. While levels of pregnancy-associated plasma protein-A and free β-subunit (fβ)-hCG were not different to those of the control group, AFP, unconjugated estriol and β-hCG concentrations were significantly different in the study group (P < 0.05), when compared to those of unaffected pregnancies. Levels of β-hCG in pregnancies with hydrops fetalis were significantly higher than in those with cystic hygroma (P <0.0001), as were AF-AFP concentrations (P <0.0015). In addition, abnormalities in both maternal serum β-hCG and AF-AFP predicted fetal death. The relative risk of adverse obstetric outcome was 10.667 (P = 0.0004; 95% confidence interval [CI]: 1.554-73.203) for β-hCG and 2.19 (P = 0.0256; 95% CI: 1.001 to 4.779), for AF-AFP.
  
  
  CONCLUSIONS
  Maternal serum β-hCG and AF-AFP levels may preferentially identify those Turner syndrome pregnancies with the highest risk of fetal death.
authors.affiliation: Instituto de Investigaciones Genéticas, Universidad del Zulia, Maracaibo, Venezuela.
authors.forename: Francisco
authors.initials: F
authors.lastname: Alvarez-Nava
authors.affiliation: Instituto de Investigaciones Genéticas, Universidad del Zulia, Maracaibo, Venezuela.
authors.forename: Marisol
authors.initials: M
authors.lastname: Soto
authors.affiliation: Unidad de Endocrinología Pediátrica, Hospital de Clínicas Caracas, Caracas, Venezuela.
authors.forename: Roberto
authors.initials: R
authors.lastname: Lanes
authors.affiliation: Centro de Medicina Experimental, Universidad del Zulia, Maracaibo, Venezuela.
authors.forename: Hector
authors.initials: H
authors.lastname: Pons
authors.affiliation: Instituto de Investigaciones Genéticas, Universidad del Zulia, Maracaibo, Venezuela.
authors.forename: Alisandra
authors.initials: A
authors.lastname: Morales-Machin
authors.affiliation: Instituto de Investigaciones Genéticas, Universidad del Zulia, Maracaibo, Venezuela.
authors.forename: Ana
authors.initials: A
authors.lastname: Bracho
mesh_terms: D000653:Amniotic Fluid / Q000737:chemistry*; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D005260:Female; D005315:Fetal Diseases; D006801:Humans; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D012372:ROC Curve; D014424:Turner Syndrome / Q000150:complications*; D000509:alpha-Fetoproteins / Q000032:analysis*
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human; D000509:alpha-Fetoproteins
keywords: Turner syndrome; adverse pregnancy outcome; biochemical screening; prenatal diagnosis