Maternal serum alpha-fetoprotein and dimeric inhibin A detect aneuploidies other than Down syndrome.

Abstract

OBJECTIVE:

Our purpose was to determine whether the combination of maternal serum alpha-fetoprotein, free human chorionic gonadotropin-beta, dimeric inhibin A, and maternal age detects aneuploidies other than Down syndrome.

STUDY DESIGN:

We retrieved stored serum from pregnancies complicated by aneuploidies other than Down syndrome from 1988 to 1997 (n = 55, mean maternal age 35.2 +/- 5.6 years). Alpha-fetoprotein levels were obtained from our database, and free human chorionic gonadotropin-beta and dimeric inhibin A levels were measured in the thawed serum with use of commercial assays. Analyte values were used in both 3-analyte and 2-analyte multiple-marker screening tests; detection rates were determined at several different Down syndrome risk-positive cutoff values.

RESULTS:

In the 3-analyte test 58% (32/55) of all aneuploidies were detected with use of both the Down syndrome protocol at a screen-positive risk cutoff value of 1:300 (false-positive rate 17%) and a novel trisomy 18 screening algorithm. However, 67% (37/55) detection was obtained with use of the 2-analyte combination of alpha-fetoprotein and dimeric inhibin A, with both the Down syndrome protocol (screen positive cutoff value 1:300) and the trisomy 18 algorithm: 12 of 13 trisomy 18 (92%), 9 of 17 Turner's syndrome (53%), 10 of 17 other sex chromosome aneuploidies (59%), 1 of 1 trisomy 22 (100%), and 5 of 7 trisomy 13 (71%).

CONCLUSIONS:

The combination of maternal serum alpha-fetoprotein, dimeric inhibin A, and maternal age detects autosomal trisomies other than Down syndrome at a rate superior to that of the traditional analyte combination.

• Authors: K D Wenstrom, D C Chu, J Owen, L Boots
• Journal: American journal of obstetrics and gynecology (Am J Obstet Gynecol) Vol. 179 Issue 4 Pg. 966-70 (Oct 1998) ISSN: 0002-9378 [Print] United States
• PMID: 9790380 (Publication Type: Journal Article)

Chemical References

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

Topics

• Adult
• Aneuploidy
• Chorionic Gonadotropin, beta Subunit, Human (blood)
• Chromosomes, Human, Pair 18
• Dimerization
• Down Syndrome (diagnosis)
• Female
• Gestational Age
• Humans
• Inhibins (blood)
• Pregnancy
• Prenatal Diagnosis (methods)
• Sex Chromosome Aberrations (diagnosis)
• Trisomy
• Turner Syndrome (diagnosis)
• alpha-Fetoproteins (analysis)