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stackedDNA-small.jpgPrenatal Genetic Screening

Every pregnant woman hopes for a healthy baby. Although most babies are healthy, it’s normal to wonder about your baby.

Prenatal screening is available to all pregnant women. A screening test does not tell for sure whether or not your baby is healthy, but it can tell if you have a lower or higher chance/risk that usual of having a baby with Down Syndrome, trisomy 18 and open neural tube defects. Please speak with your physician regarding prenatal screening.

Integrated Prenatal Screening (IPS)

Integrated Prenatal Screening is a new and improved prenatal screening test which uses an early ultrasound, measuring nuchal translucency and two blood tests to give the integrated risks of having a baby with Down’s Syndrome, trisomy 18 or open neural tube defects. IPS replaces MSS in early pregnancy.

The use of IPS offers a better detection and lower false positive rate for Down Syndrome than MSS.

Testing is done in two parts:

  • Part 1 (11 weeks 0 days to 13 weeks 6 days) - Blood test and ultrasound
  • Part 2 (15 weeks 0 days to 18 weeks 6 days)- Blood test

Maternal Serum Screening (MSS)

Maternal Serum Screening is a prenatal screening test which provides you with the risks of having a baby with Down syndrome, open neural tube defects or trisomy 18. This blood test is done after 15 weeks 0 days gestation.

What does a “screen positive” result mean?

If your result is “screen positive”, the chance/risk of your baby having Down syndrome, open neural tube defects or trisomy 18 is higher than usual. Most women with a screen positive result DO NOT have a baby with any of these conditions.

If the “screen positive” result is for Down syndrome or trisomy 18, a procedure called amniocentesis would be offered to the pregnant woman.

If the “screen positive” result is for open neural tube defect (Spina Bifida and anencephaly) you will be offered a level II ultrasound .

What does a “screen negative” result mean?

If the result is “screen negative”, further testing is not offered. IPS can sometimes miss a small number of babies with Down Syndrome, trisomy 18 or an open neural tube defect.