Sequential testing pregnancy vs quad screen

#SEQUENTIAL TESTING PREGNANCY VS QUAD SCREEN HOW TO#

You may also be told that your results are 'normal' or 'abnormal' for a particular condition, depending on whether the ratio is below or above a certain cutoff. The higher the second number, the lower the risk.

And a risk of 1 in 1,200 means that for every 1,200 women with this result, one baby will have Down syndrome and 1,199 will not.

A risk of 1 in 100 means that for every 100 women with this result, one baby will have Down syndrome and 99 will not. Each one will be in the form of a ratio that expresses your baby's chances of having that problem.ДЇor example, you may be told that your baby's chances of having Down syndrome are 1 in 100 or 1 in 1,200. You'll be given one risk assessment for Down syndrome, one for trisomy 18, and another for neural tube defects. Many centers will report individual lab results as well as the final calculated result using a special formula.

#SEQUENTIAL TESTING PREGNANCY VS QUAD SCREEN HOW TO#

Talk with your practitioner or genetic counselor about how to interpret the results, which can be confusing. How do I interpret the results of the quad screen? If you're having the quad screen as part of an integrated or sequential screening, the results will be combined with those from the tests you took in your first trimester for a more comprehensive risk assessment and a higher detection rate. To determine your baby's chances of having a neural tube defect, your level of AFP is plugged into a formula along with your age, your baby's gestational age, and other factors. For example, your likelihood of carrying a baby with Down syndrome ranges from about 1 in 1,200 at age 25 to about 1 in 100 at age 40. Your age is factored in because although anyone can have a baby with a chromosomal abnormality, the risk increases as you age. To determine your baby's chances of having Down syndrome or trisomy 18, your levels of the four substances are plugged into a formula along with your baby's gestational age and your age. Low levels of the first three means your baby has a higher than normal risk of having trisomy 18 (Edwards syndrome). Low AFP, low estriol, high hCG, and high inhibin AВ are associated with a higher risk for Down syndrome. And in some cases, it doesn't mean any of those things. In rare cases, it can also signify a problem with the baby's kidneys. But in some cases, it's a sign of an abnormal opening in the baby's spine (spina bifida), head, or abdominal wall that's allowing AFP to leak out. If there's more AFP than expected, it may mean that you're carrying more than one baby or that your baby is older than your practitioner thought. A baby produces AFP throughout gestation, and a certain amount of it should cross the placenta into the mother's bloodstream at each stage.

Inhibin A, a hormone produced by the placenta.

Unconjugated estriol (uE3), a hormone produced by the placenta and the baby.

Human chorionic gonadotropin (hCG), a hormone made by the placenta.

Alpha-fetoprotein (AFP), a protein made by the baby.

The test measures the levels of four substances in your blood: Results are usually available in about a week. You'll have a blood sample taken and sent to a lab for analysis. But if you miss the opportunity to start your screening in the first trimester, the quad screen alone can still give you some good information. This combination is known as integrated or sequential screening. Ideally, the test should be performed in conjunction with first-trimester screening tests. The quad screen is done in the second trimester, between 15 and 22 weeks of pregnancy (16 to 18 weeks is considered best). Knowing this can enable you and your practitioner to be on the lookout for signs of trouble.

Neural tube defects, such as spina bifidaД¬ertain results may also indicate that you're at a somewhat greater risk for complications such as preeclampsia, premature birth, intrauterine growth restriction, or miscarriage.

Trisomy 18 (Edwards syndrome), a more severe and less common chromosomal disorder.

Down syndrome (trisomy 21, the most common chromosomal disorder).

It's a screening test, which means it can tell you how likely it is that your baby has a condition, but you still need a diagnostic test ( amniocentesis) to confirm the results. The quad screen (sometimes referred to as the quadruple screen, AFP4, or multiple marker) is a blood test that can tell you whether your baby is at an increased risk for certain conditions.

Sequential testing pregnancy vs quad screen