Prenatal Screening
Helping our patients achieve a healthy pregnancy is our first priority, and that includes access to our reproductive geneticist and licensed, certified genetic counselor. We also offer comprehensive aneuploidy and expanded genetic disease carrier screening options. Although there is no single test that can screen for all genetic diseases, the diagnostic testing and screening procedures at Genetics & IVF Institute provide patients with valuable information about the health of their pregnancies and pregnancy-related reproductive risks.
A screening test during pregnancy provides a personalized risk assessment for certain medical conditions. Blood tests and ultrasound are commonly available genetic screening tests and they carry no risk to a pregnancy. A “negative” (normal) screening result means you have a reduced risk of having a baby with certain medical disorders but cannot guarantee a healthy pregnancy. If you have a “positive” (abnormal) result from a screening test, diagnostic testing for additional information is recommended.
Who Should Consider Prenatal Screening?
All patients are encouraged to consider screening options during their pregnancy. The decision about whether to opt for a screening test, or which screening test(s), is personal. As you consider your options, you should consider how much information you wish to gain during your pregnancy. During a consultation, your genetics specialist will outline the benefits and limitations of each test and review your personal situation so that you are comfortable with your testing decision.
Screening Tests
FTS is a noninvasive screening option available to women of all ages who are interested in early information about the health of their pregnancies. The FTS combines a specialized ultrasound examination with maternal blood testing. The FTS ultrasound looks for the presence of the fetal nasal bone and measures a tiny, fluid-filled sac at the back of the neck, called the nuchal translucency (NT). An increased NT may indicate a chromosomal disorder, other genetic syndrome, a congenital heart defect, or other congenital abnormality, but it can also be seen in normal fetuses. A maternal blood test that measures pregnancy hormones is combined with ultrasound information and maternal age to calculate a specific risk for Down syndrome and for trisomy 18 or 13. One of our genetics specialists will review your results with you and provide guidance if additional testing or fetal evaluations is recommended.
CfDNA is a blood test that provides a risk assessment for Down syndrome, trisomy 18, trisomy 13, and some sex chromosome abnormalities. This screening analyzes small quantities of placental DNA that are circulating in the maternal blood. Sometimes there is insufficient placental DNA in the maternal blood to obtain a result, making a different test more appropriate for the pregnancy. When screening for sex chromosome abnormalities, the fetal sex will be provided on your test report and can be shared with you if requested.
ECS is a blood test to determine if a pregnancy will be at increased risk of being affected with a specific genetic disease(s). Every person is expected to be a silent carrier of multiple recessive genetic diseases. When both biological parents silently carry the same disease, a pregnancy would be at a 25% risk of being affected with that disorder.
Expanded genetic carrier screening at Genetics & IVF Institute helps determine which disease(s) a person carries from a panel of selected diseases. When expanded carrier screening is performed, test results help determine to what extent the patient is at-risk for a child to be affected with a specific disease.
Results often reduce reproductive risks and provide additional reassurance for patients attempting conception. However, when results identify increased risks, patients are provided the opportunity to learn about the at-risk disease(s) and consider their reproductive planning or testing options to have a healthy child. This type of testing is most effective if performed before pregnancy.
High-resolution fetal ultrasonography (also called level II ultrasound) is recommended in all pregnancies to evaluate a fetus for the presence or absence of congenital abnormalities. In all pregnancies, there is a 3–4% chance for a fetal congenital abnormality, and this risk may be increased if there has been a previous pregnancy with a congenital abnormality or a family history of a genetic syndrome. Level II ultrasound also evaluates for markers, which are physical variations that are occasionally seen in healthy pregnancies but are more frequent in high-risk pregnancies. At Genetics & IVF Institute, if an ultrasound marker or significant physical abnormality is identified during your level II ultrasound, you will be informed immediately and will receive genetic counseling regarding the finding(s). It is important to keep in mind that some fetal abnormalities are undetectable on ultrasound even under the best circumstances.
