First Trimester Screening FAQs
Who should consider First Trimester Screening?
The FTS is recommended for pregnant women of any age who would like early information about the
health of a pregnancy without invasive testing. Serious chromosomal abnormalities are more commonly associated with pregnancies in women age 35 and older, but they can occur at any age. In fact, more babies with Down syndrome are born to women under age 35.
What is First Trimester Screening?
The FTS is a non-invasive tool that combines a blood test, a specialized ultrasound, and your age. This information provides a powerful, personalized risk assessment for your current pregnancy. It detects up to:
- 98% of pregnancies with Down syndrome, and
- 95% of pregnancies with Trisomy 18 or Trisomy 13.
This screening process is significantly more accurate and available earlier in pregnancy than the second trimester blood test (quadruple screen) for Down syndrome and other conditions. However, no screen can assess the risk for every chromosome abnormality, genetic disease, or birth defect.
How is First Trimester Screening performed?
At your FTS appointment, you will have an ultrasound and a blood draw. The blood sample is used to measure the concentration of five proteins, PAPP-A (pregnancy associated plasma protein A), free ß-hCG (free-beta human chorionic gonadotropin), AFP (alpha-feto-protein, DIA (Dimeric Inhibin A), and PGIF (Placental Growth Factor). These proteins are released into the maternal blood in every pregnancy. The ultrasound looks for the presence of the fetal nasal bone and measures the nuchal translucency. The nuchal translucency is a fluid filled area at the back of the fetal neck, present in every pregnancy.
Information from the blood test and ultrasound are combined with your age to generate your result. The personalized results will describe the risks for Down syndrome and for Trisomy 18 or Trisomy 13 in your pregnancy.
When should I have my First Trimester Screening?
The FTS ultrasound is performed during a specific window of time based on fetal size. For most women, this begins during the 11th week and continues through the 13th week of pregnancy. The blood work can be done at the same time, or in the two weeks prior to the ultrasound. For convenience, most women will have their ultrasound and blood work completed at the same appointment.
How will I receive my First Trimester Screening results?
GIVF has on-site genetic counselors who will meet with you the day of your ultrasound and call you with your FTS results, generally less than a week after your appointment. Genetic counselors have extensive training in prenatal screening and a thorough understanding of the test implications; they will explain the results to you and answer your questions.
What will my First Trimester Screening results tell me?
The genetic counselor will give you two results. The first result is the chance for Down syndrome. The second result is the chance for Trisomy 18 or Trisomy 13. These results are expressed as probabilities, such as 1 in 1000 (low risk) or 1 in 100 (high risk). The genetic counselor will explain your personalized results and what they mean for your pregnancy.
Most women’s results are normal and provide reassurance that further screening or invasive testing for chromosome abnormalities is probably not necessary. Some women may be offered further blood screening options. Other women will be offered diagnostic follow-up testing, such as chorionic villus sampling (CVS) or amniocentesis.
All follow-up options are elective. You will be able to decide what next steps (if any) are right for you based on your FTS results, pregnancy history, and personal preferences.
What else could my First Trimester Screening tell me?
Enlargement of the nuchal translucency indicates that the fetus has an increased risk for chromosome
abnormalities. An enlarged nuchal translucency can also be seen in some pregnancies with a heart defect or a rare genetic disorder. Additional testing or follow-up procedures may be recommended for later in pregnancy.
Why should I have my First Trimester Screening at GIVF?
- For your convenience, GIVF gives you the option of completing the blood work and ultrasound on the same day. Alternative scheduling can be arranged.
- You will meet with a genetic counselor on the day of your appointment. The counselor will answer your questions about the screening and inform you of your ultrasound findings. She will also speak to you about your genetic family history.
- The genetic counselor will call you directly with your FTS results. This is another opportunity to ask questions and review possible follow-up options based on the ultrasound or family history information. Genetic counselors have a Masters degree in Genetics, a national board certification, and additional training in counseling and fetal development. They discuss information, provide support, and act as patient advocates throughout the genetic screening process. As the primary contacts for patients at GIVF, genetic counselors help to coordinate testing and interpret results.
- Patients with abnormal results have immediate access to genetic counselors and often same day diagnostic testing if necessary.
- GIVF is the only local center that provides the complete range of patient support, non-invasive
screening, and diagnostic testing. This continuity of care ensures you get complete and accurate
information as quickly as possible.
- The FTS is only accurate when performed by certified professionals. The staff of GIVF is highly skilled and certified by The Fetal Medicine Foundation.
How do I schedule an appointment for my First Trimester Screening?
Contact GIVF early in your pregnancy to schedule an appointment by calling 703.698.7355 or clicking here. You will be asked to provide the due date given to you by your obstetrician when scheduling your appointment.