The triple test
The triple test is a blood test which is performed between 15 and 17 weeks of pregnancy. It tests the levels of three components in the mother's blood which have come from the placenta:
beta HCG (human chorionic gonadotrophin)
This test is actually a screening test which means that it can tell you whether the pregnancy has a high risk of Down syndrome or a low risk of Down syndrome.
It cannot tell us definitely if the pregnancy is affected. This screening test detects approximately 65% of Down syndrome pregnancies.
If the results are "high risk" then we will discuss with you further options such as a diagnostic test like amniocentesis.
The triple test is being used less and less these days, because of the availability of other screening tests with a higher detection rate.
For example, nuchal screening with nasal bone screening and first trimester serum screening detects 95% of Down syndrome when done well.
Non-invasive prenatal screening or testing (NIPS or NIPT) detects more than 99% of Down syndrome by analysis of the cell free fetal DNA (cffDNA) in a blood test of the pregnant woman.
It can be done between 10 and 40 weeks of pregnancy, but we encourage women to do it between 10 and 14 weeks' pregnancy.
Talk to us if you would like to have any of these tests in your pregnancy.