Maternal serum screening for alpha-fetoprotein, unconjugated estriol, and human chorionic gonadotropin between 11 and 15 weeks of pregnancy to detect fetal chromosome abnormalities

Am J Obstet Gynecol. 1993 Jun;168(6 Pt 1):1864-7; discussion 1867-9. doi: 10.1016/0002-9378(93)90703-l.

Abstract

Objective: The purpose of this prospective study was to assess the value of maternal serum screening between 11 and 15 weeks of gestation to detect fetal Down syndrome.

Study design: Blood samples were collected on 993 women between 11 and 15 weeks' gestation before amniocentesis. Ninety percent were > or = 35 years old. Samples were coded and assayed for alpha-fetoprotein, unconjugated estriol, and human chorionic gonadotropin. Medians were established at each week between 11 and 15 from 836 normal, singleton pregnancies.

Results: We used a computer-generated cut-off risk for Down syndrome of one in 365 at term; nine of 11 (82%) Down syndrome pregnancies were identified. There were 23% false-positive results in women > or = 35 years old and 6% in those < 35 years.

Conclusion: These results suggest that maternal serum screening between 11 and 15 weeks may provide an acceptable alternative to screening between 16 and 20 weeks.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Chorionic Gonadotropin / blood*
  • Chromosome Aberrations / diagnosis*
  • Chromosome Disorders
  • Down Syndrome / diagnosis
  • Estriol / blood*
  • False Positive Reactions
  • Female
  • Humans
  • Pregnancy / blood*
  • Pregnancy Trimester, First
  • Prenatal Diagnosis*
  • Prospective Studies
  • Risk Factors
  • alpha-Fetoproteins / analysis*

Substances

  • Chorionic Gonadotropin
  • alpha-Fetoproteins
  • Estriol