Put pressure on the site and then put on a bandage. How accurate is it? The triple and quad tests correctly find neural tube defects, such as spina bifida, in 80 out of fetuses who have it and find anencephaly in about 90 out of fetuses. The triple test correctly finds Down syndrome in 69 out of fetuses who have it.
It misses the condition in 31 out of fetuses. It misses Down syndrome in 19 out of fetuses. What do the results mean? What do you do with the results? Should you have the triple or quad screening? Health Tools Health Tools help you make wise health decisions or take action to improve your health. Decision Points focus on key medical care decisions that are important to many health problems. Spina Bifida. References Citations Cunningham FG, et al. Prenatal diagnosis and fetal therapy.
In Williams Obstetrics , 23rd ed. American College of Obstetricians and Gynecologists , reaffirmed Screening for fetal chromosomal abnormalities. Obstetrics and Gynecology , 1 : — Credits Current as of: February 11, Top of the page Next Section: Health Tools.
Previous Section: References Top of the page. Current as of: February 11, Cunningham FG, et al. Obstetrics and Gynecology , 1 : There can be multiple reasons for high levels of AFP in the blood. Some of the key reasons are listed below. Birth defect — quadruple, uE3 — quadruple, Unconjugated estriol — quadruple, Pregnancy — quadruple, AFP plus, AFP maternal, Triple screen test, 4-marker screen, Trisomy 21 — quadruple, Down syndrome — quadruple, Turner syndrome — quadruple, Tetralogy — quadruple, Spina bifida — quadruple, Duodenal atresia — quadruple.
State Location Phone No. Quad Screen Test Quad Screen or Quadruple marker is a blood test done during the second trimester weeks of pregnancy to identify some chromosomal abnormalities birth defects in the unborn baby. Human chorionic gonadotropin hCG ; a hormone produced by the placenta Alpha-fetoprotein AFP ; a protein produced by the growing baby. Inhibin A; a hormone produced by the placenta Unconjugated Estriol UE ; a hormone produced by baby's liver and placenta The levels of the above-mentioned substances keep changing every week, during the pregnancy.
What are the risks? How to prepare for the procedure? Expected results from the test: FAQ Section:. Quad screen is performed to identify the birth disorders and the risks of continuing pregnancy. Abnormal Results : A positive or abnormal Quad test is attributed to the following reasons: Not calculating the correct time or the week of pregnancy In vitro fertilization Numerous pregnancies Diabetic condition Smoking during the pregnancy If the result is positive, the woman is advised to go for an ultrasound test, which will further confirm the number of babies and the gestational age.
Amniocentesis — The test examines the amniotic fluid around the baby and the AFP levels. Targeted ultrasound — A patient is usually advised, by the doctor, to go for an Ultrasound if the Quad test comes positive. However, USG cannot pick up all cases of Down syndrome. The screen is essentially the same as the screening tests that look for only three substances, except the likelihood of identifying pregnancies at risk for Down Syndrome is higher through the evaluation of Inhibin-A levels.
The false-positive rate of the test is also lower. It is very important to remember what a screening test is before getting one performed.
This will help alleviate some of the anxiety that can accompany test results. Screening tests do not look only at results from the blood test. The quad screen test involves drawing blood from the mother, which takes about 5 to 10 minutes. The blood sample is then sent to the laboratory for testing. The results usually take a few days to receive. Except for the discomfort of drawing blood, there are no known risks or side effects associated with the quad screen test.
The quad screen test is performed between the 16th and 18th week of pregnancy. All pregnant women should be offered the quad screen, but it is recommended for women who:. High levels of AFP may suggest that the developing baby has a neural tube defect such as spina bifida or anencephaly.
Low levels of AFP and abnormal levels of hCG and estriol may indicate that the developing baby has Trisomy 21 Down syndrome , Trisomy 18 Edwards Syndrome or another type of chromosome abnormality. It is important to remember that the quad screen is a screening test and not a diagnostic test. The quad screen correctly identifies about 80 percent of women who are carrying a baby who has Down syndrome. About 5 percent of women have a false-positive result, meaning that the test result is positive but the baby doesn't actually have Down syndrome.
When you consider your test results, remember that the quad screen only indicates your overall chance of carrying a baby who has certain chromosomal conditions, neural tube defects or abdominal wall defects. A decreased chance negative screen result doesn't guarantee that your baby won't have one of these conditions. Likewise, an increased chance positive screen result doesn't guarantee that your baby will be born with one of these conditions.
Your health care provider or a genetic counselor will help you understand your test results and what the results might mean for your pregnancy. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. This content does not have an English version. This content does not have an Arabic version. Sections for Quad screen About. Overview The quad screen — also known as the quadruple marker test, the second trimester screen or simply the quad test — is a prenatal test that measures levels of four substances in pregnant women's blood: Alpha-fetoprotein AFP , a protein made by the developing baby Human chorionic gonadotropin HCG , a hormone made by the placenta Estriol, a hormone made by the placenta and the baby's liver Inhibin A, another hormone made by the placenta.
More Information Prenatal testing: Quick guide to common tests. Request an Appointment at Mayo Clinic. Share on: Facebook Twitter. Show references AskMayoExpert.
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