QuestionSBA
QuestionChoice
Oestradiol is not tested for as part of combined screening.
49911
e
Oestradiol
QuestionChoice
Alpha-fetoprotein (AFP) is performed as part of the triple screening test, which is performed later in pregnancy, after 13 weeks. AFP is reduced in pregnancies with Down syndrome.
49908
b
Alpha-fetoprotein (AFP)
QuestionChoice
Beta-hCG is tested as part of the combined screening test, alongside nuchal translucency and pregnancy-associated plasma protein-A (PAPP-A). The combined test gives an overall risk of Down syndrome.
49907
a
Beta-hCG
QuestionChoice
Amniotic fluid level is not tested for as part of combined screening.
49910
d
Amniotic fluid level
QuestionChoice
Pregnancy-associated plasma protein-A (PAPP-A) is tested as part of the combined screening test, alongside beta-hCG and nuchal translucency. Pregnancy-associated plasma protein-A (PAPP-A) is reduced in pregnancies with Down syndrome.
49909
c
Pregnancy-associated plasma protein-A (PAPP-A)
Concept
Chapter
# Summary


Screening for Down Syndrome in pregnancy typically involves the use of the Combined Test, Triple Test, or Quadruple Test. These tests measure various hormones and proteins in the blood and use ultrasound scanning to provide a risk score. A high-risk result may warrant further diagnostic tests, such as chorionic villus sampling or amniocentesis, for a definitive answer. 

# Combined test

The recommended screening test for Down Syndrome is the combined test, which measures:

- Nuchal translucency using ultrasound scan
- PAPP-A hormone (level reduced in pregnancy affected with Down's syndrome)
- Beta-hCG hormone (raised in pregnancy affected by Down's syndrome)

The combined test is carried out between 11 and 13 weeks of pregnancy in the first trimester and combination of these components is used to provide a risk score.

Where the combined test is unavailable or the woman attends presents for the first time after 13 weeks gestation, the triple test or quadruple test is offered which involve a blood test to measure hormone levels.

# Triple test

The triple test:

- Beta-hCG
- AFP (reduced in pregnancies affected by Down syndrome)
- uE3 (reduced in pregnancies affected by Down syndrome)

# Quadruple test

The quadruple test is the triple test but with the addition of Inhibin-A levels (raised in pregnancies affected by Down syndrome).

# Further tests

Note that these screening tests will only give a result of increased or decreased risk of having a baby with Down syndrome compared to the normal population. Women with a high risk result may be offered a diagnostic test such as chorionic villus sampling or amniocentesis to provide a definitive answer.
91
93
Down's Syndrome Screening
Topic
38
Obstetrics
10018
Presentation
459
Pregnancy risk assessment
UkmlaTopic
4
Cardiovascular
Presentation
460
Pregnancy risk assessment
UkmlaTopic
18
Obstetrics and gynaecology
A 42-year-old woman attends her general practitioner after finding out she is pregnant. Her last menstrual period was six weeks ago. She is aware that having a pregnancy in her 40's is higher risk for Down syndrome and is keen to "get tested" as soon as possible.

She is offered the combined test at 11 weeks. Which of the following is a component of combined screening that, if raised, may indicate a higher risk of Down syndrome?
a