Prospective evaluation of free beta-subunit of human chorionic gonadotropin and dimeric inhibin A for aneuploidy detection.

Abstract

OBJECTIVE:

Our goal was to prospectively evaluate the use of the free beta-subunit of human chorionic gonadotropin and dimeric inhibin A for the detection of fetal Down syndrome and other aneuploidies.

STUDY DESIGN:

Women who had a second-trimester multiple-marker screening test (alpha-fetoprotein, unconjugated estriol, human chorionic gonadotropin) and genetic amniocentesis from August 1996 to August 1998 were included. Serum was also analyzed for inhibin and the free beta-subunit of human chorionic gonadotropin. Detection and false-positive rates for 4 analyte combinations at 5 different screening risk cutoff points for Down syndrome were determined and compared.

RESULTS:

We evaluated 1256 patients, including 23 with aneuploidy (13 with Down syndrome, 10 others). The maternal age was 35.9 +/- 4.6 years (mean +/- SD). At the optimal risk cutoff point for Down syndrome detection (1:190; false-positive rate, 19%), the multiple-marker screening test plus inhibin was superior, detecting 85% of Down syndrome cases, in comparison with 69% when the multiple-marker screening test alone was used and 62% when the other 2 combinations were used. The multiple-marker screening test plus inhibin also detected 60% of the other aneuploidies.

CONCLUSIONS:

When evaluated prospectively in a high-risk population, the multiple-marker screening test plus inhibin was superior to the traditional multiple-marker screening test and 2 other analyte combinations, with a lower false-positive rate and increased detection of all aneuploidies in a high-risk population.

• Authors: K D Wenstrom, J Owen, D c Chu, L Boots
• Journal: American journal of obstetrics and gynecology (Am J Obstet Gynecol) Vol. 181 Issue 4 Pg. 887-92 (Oct 1999) ISSN: 0002-9378 [Print] United States
• PMID: 10521748 (Publication Type: Journal Article)

Chemical References

• Chorionic Gonadotropin
• Chorionic Gonadotropin, beta Subunit, Human
• alpha-Fetoproteins
• Inhibins
• Estriol

Topics

• Amniocentesis
• Aneuploidy
• Chorionic Gonadotropin (blood)
• Chorionic Gonadotropin, beta Subunit, Human (blood)
• Dimerization
• Down Syndrome (diagnosis)
• Estriol (blood)
• False Positive Reactions
• Female
• Gene Deletion
• Humans
• Inhibins (blood)
• Pregnancy
• Prenatal Diagnosis (methods)
• Prospective Studies
• Translocation, Genetic
• Trisomy
• alpha-Fetoproteins (analysis)