California Prenatal Screening Program

The California Prenatal Screening Program offers three screening options to identify women who are more likely to be carrying a fetus with certain birth defects. The screening program is offered to all pregnant women in California, but the decision about whether or not to have a screening test, or which screening test to choose, is up to you.

The three screening tests offered through the California Prenatal Screening Program include: Quad Marker Screening, Serum Integrated Screening, and Sequential Integrated Screening. All three tests provide an estimate of risk for Down syndrome, trisomy 18, open neural tube defects, abdominal wall defects, and Smith-Lemli-Opitz syndrome.  The main difference among the tests is the specific information used to help define a woman's risk.

• Quad Marker Screening - Uses a single blood test to measure four fetal proteins naturally found in the mother's blood. The blood test is done between 15 weeks and 20 weeks.

• Serum Integrated Screening - Uses two blood tests to measure a total of six fetal proteins naturally found in the mother's blood. The first blood test is done between 10 weeks and 13 weeks 6 days; the second blood test is done between 15 weeks and 20 weeks. The second blood test is the same one used for Quad Marker Screening.

• Sequential Integrated Screening - Uses the same two blood tests as Serum Integrated Screening and a nuchal translucency (NT) ultrasound. The NT ultrasound is done between 11 weeks 2 days and 14 weeks 2 days.

You can find more about the California Prenatal Screening Program on their website: www.cdph.ca.gov/programs/pns 

Last reviewed: January 11, 2013
Reviewed by: Kaiser Permanente Genetics