Analysis of Second Trimester Maternal Quadruple Screening Test for Trisomy 21 and Trisomy 18
Abstract
Background: The second trimester quadruple screening test for foetal chromosomal abnormalities has been carried out in Slovenia since 2006. Our objective was to analyse the quadruple test results, define sensibility and specificity, the positive and negative predictive value of the screening test for trisomy 21 and trisomy 18 and the influence of some maternal clinical parameters on risk calculation.
Methods: Retrospectively collected results of 3,719 maternal blood samples were analysed in the period from February 1st, 2006 to December 31st, 2009 at the University Medical Centre Ljubljana. We obtained information on maternal age, body weight and smoking (habits?), karyotyping of foetuses and clinical data on newborns.
Results: The sensitivity of the test for trisomy 21 was 50%, specificity 95%, positive predictive value 2.3% and negative predictive value 99.8%. Specificity for trisomy 18 was 98%, sensitivity 100% and the positive and negative predictive value 1.4% and 100% respectively.. False positive results in trisomy 21 were influenced by maternal weight (OR=1.034; p=0.00) and age (OR=0.832; p=0.00). It was influenced by maternal age (OR=0.924; p=0.17) and smoking (OR=0.396; p=0.006) in the case of trisomy 18.
Conclusions: A quadruple test has an appropriate specificity for detecting foetuses with trisomy 21; however, it displays a low sensibility as well as a low positive predictive value. The test reveals high specificity and sensibility for the detection of foetal trisomy 18, and has a high negative predictive value, yet its positive predictive value remains low. Therefore, the test is primarily intended for pregnant women who, for various reasons, missed out on screening opportunities in the first trimester of their pregnancy.
Downloads
References
Tul N. Presejalni hormonski testi za Downov sindrom. Med Razgl 1997; 36: 523-37.
Tul N. Presejanje za kromosomopatije pri plodu. Med Razgl 2011; 50 Suppl 2: 137-48.
Van Lith JM, Pratt JJ, Beekhuis JR. Second-trimester maternal serum immunoreactive inhibin as a marker for fetal Down’s syndrome. Prenat Diagn 1992; 12: 801-6.
Merkatz IR, Nitowsky HM, Macri JN. An association between low maternal serum alpha-fetoprotein and fetal chromosomal abnormalities. Am J Obstet Gynecol 1984; 148: 886-94.
Brock DHJ, Bolton AE, Monaghan JM. Prenatal diagnosis of anencephaly through maternal serum alpha- fetoprotein measurment. Lancet 1973; ii: 943–4.
Merkatz IR, Nitowsky HM, Macri JN, Johnson WE. An association between low maternal serum alpha- fetoprotein and chromosomal abnormalities. Am J Obstet Gynecol 1984; 148: 886–94.
Pajntar M, Novak-Antolič Ž in sodelavci. Nosečnost in vodenje poroda, 2. dopolnjena izd. Ljubljana: Cankarjeva založba; 2004.
Cuckle HS, Wald NJ, Lindenbaum RH. Maternal serum alpha-fetoprotein measurement: a screening test for Down syndrome. Lancet 1984; i: 926–9.
Wald NJ, Hackshaw AK, George LM. Assay precision of serum alpha fetoprotein in antenatal screening for neural tube defects and Down's syndrome. J Med Screen 2000; 7:74-7.
Canick JA, Knight GJ, Palomaki GE. Low second trimester maternal serum
unconjugated oestriol in pregnancies with Down's syndrome. Br J Obstet Gynaecol 1988; 95: 330-3.
Wald NJ, Cuckle HS, Densem JW. Maternal serum unconjugated oestriol as an antenatal screening test for Down's syndrome. Br J Obstet Gynaecol 1988; 95: 334-41.
Wald NJ, Cuckle HS, Densem JW. Maternal serum screening for Down's syndrome in early pregnancy. BMJ 1988; 297: 883–7.
Goodburn SF, Yates JRW, Raggatt PR. Second-trimester maternal serum screening using alpha-fetoprotein, human chorionic gonadotrophin, and unconjugated oestriol: experience of a regional programme. Prenat Diagn 1994; 14: 391–402.
Bogart MH, Pandian MR, Jones OW. Abnormal maternal serum chorionic gonadotropin levels in pregnancies with fetal chromosome abnormalities. Prenat Diagn 1987; 7: 623–30.
Benn PA, Fang M, Egan JF. Incorporation of Inhibin-A in Second-Trimester Screening for Down Syndrome. Obstet Gynecol 2003; 101: 451-4.
Lambert-Messerlian GM, Canick JA. Clinical application of inhibin a measurement: prenatal serum screening for Down syndrome. Semin Reprod Med 2004; 22: 235-42.
Geršak K. Načela in lastnosti presejalnih testov. Med Razgl 2011; 50 Suppl 2:19-24.
Gilbert RE, Augood A, Gupta R, Ades EA, Logan S. Screening for Downs syndrome: effects, safety and cost effectiveness of first trimester strategies. BMJ 2001; 323: 324-6.
Güdücü N, Gönenç G, Işçi H, Yiğiter AB, Dünder I. Can quadruple test parameters predict SGA infants? J Obstet Gynaecol 2013; 33: 269-71.
Lao MR, Calhoun BC, Bracero LA. The ability of the quadruple test to predict adverse perinatal outcomes in a high-risk obstetric population. J Med Screen 2009; 16:55-9.
Aagaard-Tillery KM, Malone FD, Nyberg DA. Role of second-trimester genetic sonography after Down syndrome screening. Obstet Gynecol 2009; 114: 1189-96.
Novak–Antolič Ž. Psihične obremenitve pri presejalnih testih v nosečnosti. V: Bregant L, ur. Strah,bolečina, žalost. Zbornik prispevkov. Ljubljana: GK; 1997. p. 15–22.
The Author transfers to the Publisher (Zdravniški vestnik/Slovenian Medical Journal) all economic copyrights following form Article 22 of the Slovene Copyright and Related Rights Act (ZASP), including the right of reproduction, the right of distribution, the rental right, the right of public performance, the right of public transmission, the right of public communication by means of phonograms and videograms, the right of public presentation, the right of broadcasting, the right of rebroadcasting, the right of secondary broadcasting, the right of communication to the public, the right of transformation, the right of audiovisual adaptation and all other rights of the author according to ZASP.
The aforementioned rights are transferred non-exclusively, for an unlimited number of editions, for the term of the statutory
The Author can make use of his work himself or transfer subjective rights to others only after 3 months from date of first publishing in the journal Zdravniški vestnik/Slovenian Medical Journal.
The Publisher (Zdravniški vestnik/Slovenian Medical Journal) has the right to transfer the rights, acquired parties without explicit consent of the Author.
The Author consents that the Article be published under the Creative Commons BY-NC 4.0 (attribution-non-commercial) or comparable licence.