Between the 11th and 13th week your pregnancy, your doctor may suggest an ultrasound to measure the fetus’ nuchal translucency, i.e. the subcutaneous space between the neck and the cervical spine. If this space is larger than normal, the risk of Down syndrome is high, and the risk of other chromosome abnormalities or heart defects is also high. The nuchal translucency exam must be combined with a blood test. (We recommend that the appointment be made between the 12th and 13th week of your pregnancy).
A recommended examination
The Society of Obstetricians and Gynaecologists of Canada recommends this prenatal screening examination for all women who are between 11 and 13 weeks pregnant, and all women under age 40 who have a low risk of giving birth to a baby with a physical or mental disability.
Please note that Health Canada recommends that parents do not expose their baby to ultrasound for non-medical purposes (e.g. to capture a souvenir video). The department has published Guidelines for the Safe Use of Diagnostic Ultrasound, which states that ultrasound should not be used for the following purposes:
- Taking a picture of the fetus for a non-medical reason
- Determining the sex of the baby for a non-medical reason
- Taking pictures or videos of the fetus for commercial purposes, such as a trade show
At Imagix™, we adhere to the guidelines set out by Health Canada and encourage the use of obstetric ultrasound for medical purposes.
Two types of prenatal screening
PRENATESTTM Prenatal Screening
Imagix™ offers you the Prenatest™ screening service during the first trimester of your pregnancy. The test is designed for all pregnant women, regardless of age, and does not pose any danger to the mother or the fetus. Please note that there is a fee for this service.
The simple and quick test involves taking a few drops of blood from the tip of your finger, along with a nuchal ultrasound. Prenatest™ allows us to determine your risk of carrying a fetus that may have one of the two most common congenital anomalies: trisomy 21 (Down syndrome) or trisomy 18.
Trisomy 21 Prenatal Screening Program of Quebec
This program makes the Trisomy 21 prenatal screening test available to you at no charge. Ask your doctor about the procedure to follow.
You must meet certain conditions to take the test. All pregnant women, regardless of age, can take the test. However, women with a multiple pregnancy, i.e. carrying more than one baby, cannot use the program because of the current limitations of the screening test. If this is your case, talk to your doctor about the various options available to you.
Preparing for the examination
To properly prepare for your nuchal ultrasound, it is important to drink two 8-ounce glasses of water (500 mL) one hour before the examination and not urinate.
May I be accompanied by someone for my appointment?
Even during the pandemic, a person of your choice can accompany you during this exam. If you come accompanied, be informed that this person will have to answer the same screening questionnaire as you will have to, and access could be refused.