Pregnancy is an exciting time that can also be filled with questions and concerns about the health of your developing baby. While most babies are born healthy, there is always a small chance for genetic conditions to occur, regardless of age or family history. ClariTest™ Core, a non-invasive prenatal screen (NIPS), can be an important step in your prenatal care and can provide you and your healthcare provider with valuable information about your pregnancy.
ClariTest Core is a simple blood test, which can be drawn as early as 10 weeks of pregnancy and up to delivery and screens for the most common chromosomal conditions, including:
McDonald-McGinn, D. M. & Sullivan, K. E. (2011). Chromosome 22q11.2 deletion syndrome (DiGeorge syndrome/velocardiofacial syndrome). Medicine, 90(1), 1–18.
What is a trisomy?
Each cell of our body typically has 23 pairs of chromosomes, which are the structures that hold all of our genetic information. Developmental problems and physical birth defects can occur when a person has extra or missing chromosomes. Trisomy occurs when a person has an extra chromosome, or three copies of a chromosome instead of the usual two. Trisomies are named based on which chromosome has three copies. For example, a person with trisomy 21 has an extra copy of chromosome 21.
What are sex chromosome aneuploidies (SCA)?
The X and Y chromosomes determine an individual’s sex. Females typically have two X chromosomes and males have one X and one Y chromosome. People with SCAs have a different number of X and/or Y chromosomes. Turner syndrome, or Monosomy X, occurs when there is only one female sex chromosome, instead of the normal two in a female. Depending on the condition, SCAs can cause learning difficulties, infertility, and birth defects. In general, these conditions are milder than other trisomies.
What is a 22q11.2 microdeletion?
The term microdeletion refers to a small, missing piece of a chromosome. A 22q11.2 microdeletion indicates there is a small piece of chromosome 22 missing. A deletion in this area can cause 22q deletion syndrome, also known as DiGeorge syndrome, which is the most common genetic cause of intellectual disability and heart defects after Down syndrome.1
What are my possible ClariTest Core results?
Low risk result. This means there is a low chance for the pregnancy to have any of the conditions included in this screening test. The majority of women will receive a low-risk result.
High risk result. This means there is a high chance for a chromosomal condition in the pregnancy. Invasive prenatal tests, such as chorionic villus sampling (CVS) and amniocentesis, provide definitive diagnostic information and are recommended to confirm any high-risk ClariTest Core result.
No result is obtained. In a small percentage of cases, no result is obtained. In these instances, your provider may discuss the option for a repeat blood draw or may offer you other screening or diagnostic testing options.
It is important to remember that ClariTest Core is a screening test and, while the test is highly accurate, false positive results can occur. Likewise, rare false negative results also occur, so a low risk result does not entirely rule out the possibility of a chromosome abnormality.
Why choose ClariTest Core?
ClariTest Core is performed using the most widely studied NIPS method, with over 60 published studies demonstrating its accuracy. Greater than 99% of pregnancies with Down syndrome will be detected, and less than one in 1,000 women will receive a false positive result.2
Is ClariTest Core right for me?
Based on recommendations by American College of Obstetricians and Gynecologists and Society for Maternal-Fetal Medicine, all pregnant women, regardless of age or baseline risk, have the option of choosing NIPS.³ It may be an option for you to consider if you have a confirmed singleton or twin pregnancy of at least 10 weeks gestational age and meet any of the following criteria:
You are interested in screening for common chromosome abnormalities as part of your routine pregnancy screening
You are considered to be of advanced maternal age at time of delivery (35 years or older for a singleton pregnancy or 32 years or older for a twin pregnancy)
You have an abnormal or “positive” maternal serum screen
Your ultrasound shows concerns or abnormalities with fetal growth and/or development
You have a personal or family history suggestive of trisomies 21, 18, 13, or other sex-linked chromosome abnormalities
What is genetic counseling?
Genetic counseling gives you information about how genetic conditions might affect you or your family. The genetic counselor or other healthcare professional will collect your personal and family health history. They can use this information to determine how likely it is that you or your family member has a genetic condition. Based on this information, the genetic counselor can help you decide whether a genetic test might be right for you or your relative.
Rauch, et al. Am J Med Genet. 2006;140:2063-2074.
Stokowski, et al. Prenatal Diagn. 2015; 35:1243-46.
Rose NC et al. Am J Obstet Gynecol. 2020;136(4):e48-69.
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