Integrated test during pregnancy

The integrated test is done during pregnancy to check for Down syndrome and open neural tube problems. The test is done in two stages at two different times during the pregnancy.

• The first stage is done between weeks 10 and 13. The tests done for this stage are:
  • An ultrasound. The ultrasound can show the age of the baby and measure the thickness of the skin at the back of the baby's neck (nuchal translucency, NT).
  • A blood test to measure the level of pregnancy associated plasma protein-A (PAPP-A).
• The second stage is done between weeks 15 and 16. The tests done for this stage are all blood test and include:
  • Alpha-fetoprotein (AFP).
  • Free beta-human chorionic gonadotrophin (hCG).
  • Unconjugated estriol (a form of estrogen).
  • Inhibin A.

The results of all these tests are reviewed to see if levels are higher or lower than expected. Low levels of PAPP-A, AFP, and estriol and high levels of inhibin A, hCG, and nuchal translucency may mean Down syndrome or neural tube defects are present.