The quadruple test (known too as the quadruple screen test or quadruple blood test) is a screening test done in the second trimester of pregnancy between 14 and 20 weeks. The reason for this screening test is that it checks your chances of having a baby born with Down’s syndrome.

If you are past the 13th week of pregnancy and didn’t have the double marker test conducted in the first trimester, you can have the risk assessment done through a blood test. This is known as a Quadruple marker test which can be performed between the 15th and 21st week of pregnancy.

Quad screen results give the level of risk of carrying a baby who has certain conditions compared with the general population’s risk. Keep in mind that a positive quad screen simply means that levels of some or all of the substances measured in your blood were outside the normal range.