Editing Triple test (section)

==Interpretation==
The levels may indicate increased risk for certain conditions or may be benign:

{| class="wikitable"
| '''[[alpha-fetoprotein|AFP]]''' || '''UE<sub>3</sub>''' || '''[[Human chorionic gonadotropin|hCG]]''' || '''Associated conditions''' 
 |- 
 | low || low || high || [[Down syndrome]]
 |- 
 | low || low || low  || [[trisomy 18]] ([[Edward's syndrome]])
 |- 
 | high || n/a || n/a  || [[neural tube defects]] (like [[spina bifida]] that may have associated increased levels of [[acetylcholinesterase]] in the amnionic fluid), [[omphalocele]], [[gastroschisis]], [[multiple gestation]] (like [[twins]] or [[Multiple birth|triplets]]), or an underestimation of [[Gestational age (obstetrics)|gestational age]].
|}

An estimated risk is calculated and adjusted for the expectant mother's [[Ageing|age]];<ref name="titleDowns Syndrome Screening at Nottingham City Hospital">{{cite web |url=http://www.nuh.nhs.uk/nch/clinpath/resources/downs/default.htm |title=Downs Syndrome Screening at Nottingham City Hospital |accessdate=2007-12-20 |url-status=dead |archive-url=https://web.archive.org/web/20080612221254/http://www.nuh.nhs.uk/nch/clinpath/resources/downs/default.htm |archive-date=2008-06-12 }}</ref> if she is diabetic; if she is having twins or other multiples, and the gestational age of the fetus. Weight and ethnicity may also be used in adjustments.<ref name="ReferenceA">Henry's Clinical Diagnosis and Management by Laboratory Methods, 22nd ed. Chapter 25</ref> Many of these factors affect the levels of the substances being measured and the interpretation of the results:<ref name="ReferenceA"/>

* As maternal weight increases, [[MSAFP]] level decreases
* African-American women have [[MSAFP]] levels that are 10-15% higher than those of Caucasian women for unknown reasons 
* Women with insulin-dependent diabetes mellitus have MSAFP levels that are 20% lower than the rest of the population
* Having multiple gestations, such as twins, increases MSAFP because each fetus secretes its own AFP
* Incorrect estimation of gestational age is the most common cause of abnormal MSAFP levels
[[File:Prenatal Down syndrome screening algorithm.png|thumb|An example of an algorithm for indications for further testing depending on the outcome of non-genetic blood tests including the triple test.<ref>Diagram by Mikael Häggström, using following source: {{cite web|url=https://www.uptodate.com/contents/should-i-have-a-screening-test-for-down-syndrome-during-pregnancy-beyond-the-basics/print|title=Patient education: Should I have a screening test for Down syndrome during pregnancy? (Beyond the Basics)|website=UpToDate|author=Jacquelyn V Halliday |author2=Geralyn M Messerlian |author3=Glenn E Palomaki }} This topic last updated: Feb 16, 2023.</ref>]]
The test is for [[Screening (medicine)|screening]], not for [[medical diagnosis|diagnosis]],<ref name="pmid18041410">{{cite journal |vauthors=Lamlertkittikul S, Chandeying V |title=Experience on triple markers serum screening for Down syndrome fetus in Hat Yai, Regional Hospital |journal=J Med Assoc Thai |volume=90 |issue=10 |pages=1970–6 |year=2007 |pmid=18041410 }}</ref> and does not have nearly the same predictive power as that of genetic blood testing (testing [[cell-free fetal DNA]], or invasive [[genetic testing]] which are performed by [[amniocentesis]] or [[chorionic villus sampling]]. The screening test carries a much lower risk to the [[fetus]] than invasive testing, however, and in conjunction with the age-related risk of the patient it is useful to help determine the need for more invasive tests.