Reasons for testing

Understanding your testing options helps you prepare for the future.

Your reasons for testing may include:

concerns regarding Down syndrome and trisomy 18
concerns regarding open neural tube defects in pregnancy, such as spina bifida
a family history of Down syndrome, trisomy 18, or open neural tube defects

If you are not sure whether you should have SerumIntegratedScreen^SM, please talk with your doctor, a genetic counselor or other specialist in genetics. See “Questions to Ask Your Doctor”.

Testing for...

SerumIntegratedScreen^SM screens for:

Down syndrome and trisomy 18.
Open neural tube defects, such as spina bifida and anencephaly.

How the test works

In both the first and second trimester of your pregnancy, a small amount of your blood is drawn and certain proteins and hormones are measured.

These proteins and hormones are made by your body, the developing baby and the placenta, and are found in every pregnant woman’s blood. However, when a fetus is at risk for Down syndrome or trisomy 18, or an open neural tube defect, the amount of these proteins may be abnormal.

What's not detected

Every pregnancy has some risk (3-5%) for the kinds of birth defects that cannot be diagnosed during pregnancy, such as autism, non-specific mental retardation, some genetic diseases, and some types of physical birth defects.

Understanding results

A screening test does not provide a diagnosis; it predicts the likelihood of a problem to occur. SerumIntegratedScreen^SM tells you if there is an increased risk of your baby having Down syndrome, trisomy 18 or an open neural tube defect.

Since the first and second trimester results are combined, your risk assessment is available after your second trimester blood work is complete.

SerumIntegratedScreen^SM leads to the detection* of approximately:

87% of Down syndrome cases
90% of trisomy 18 cases
80% of open neural tube defects

The result “screen negative” means there is a low risk of your baby having Down syndrome, trisomy 18 or an open neural tube defect. However, in approximately 10% of pregnancies, these birth defects will not be detected through screening.

The result “screen positive” means there is an increased risk of your baby having Down syndrome, trisomy 18 or an open neural tube defect. The next step is to talk with your doctor and/or genetic counselor about your results and your diagnostic testing options.

Some factors influencing your result:

exactly how far along you are in your pregnancy when the blood sample is taken and the ultrasound is performed
your weight, ethnic background and age
whether you are an insulin-dependent diabetic or take certain types of medications
whether you have had a previous pregnancy or a close relative affected with Down syndrome, trisomy 18 or spina bifida

If a screening test is positive, it does not mean your baby has a birth defect. In fact, most women who have positive screening results have healthy babies.

Screening testing helps doctors to identify women who should be offered additional testing. Your doctor may recommend:

a more detailed ultrasound examination (which can often identify an open neural tube defect)
diagnostic testing, such as amniocentesis for chromosome abnormalities and open neural tube defects or chorionic villi sampling (CVS) for chromosome abnormalities.