Nuchal Screening
First Trimester Screening is a method of screening during early pregnancy to determine whether your baby is at low or high risk for being affected with Down Syndrome or certain other chromosome or heart abnormalities.
The testing involves an early pregnancy ultrasound between 11 and 14 weeks gestation to look at the area around your baby’s neck, followed by a blood test. At the time of this abdominal ultrasound, an assessment of your baby’s anatomy is also performed but this is limited because of the early gestational age.
First Trimester Screening FAQ
What is a “nuchal translucency?”
Every fetus has some fluid present at the back of the neck. The thickness of this fluid can be measured and is called the nuchal translucency (NT) measurement. Fetuses affected by Down Syndrome often have an increased NT thickness as do some babies with other chromosome or heart abnormalities. The NT measurement plus the blood work will determine whether the pregnancy is “screen positive” or “screen negative.” The arrow in the photo below indicates the nuchal translucency.
What is “screen negative?”
The majority of pregnancies will be “screen negative” — the results are reassuring and further testing for chromosome abnormalities is generally not advised. It is important to realize that being “screen negative” does not alter routine prenatal care.
What is “screen positive?”
Approximately 5% of pregnancies will be “screen positive.” This means that the fetus is at higher risk of having an abnormality and that further tests will be offered, such as amniocentesis or chorionic villus sampling (CVS). Being
“screen positive” does not mean that the fetus has an abnormality, just that further testing may be needed. It is important to remember that most women that are “screen positive” actually have normal fetuses.
Why choose Genesis instead of a Provincial Screening Program?
About the Provincial Screening Program…
As of February 16, 2009, all women are eligible for Serum Integrated Preantal Screening (SIPS), regardless of their age. SIPS involves two separate blood tests. The first blood test is collected in the first trimester (10-13+6 weeks), followed by a second blood test in the second trimester (15-20+6 weeks). Results are available within 10 days after the second blood test.
Women age 40 or older at their age of delivery, and a select group of other women with a specific prenatal history are eligible for a nuchal transluceny through the province. When the nuchal translucency is combined with SIPS, it is called Integrated Prenatal Screening (IPS). Results for this test are also are available within 10 days after the second blood test.
For more information on current screening options through the province, please visit the BC Prenatal Genetic Screening Program website.
About the Genesis Screening Program…
1. First Trimester Screening (blood test & nuchal translucency)
At Genesis we offer both a blood test and a nuchal translucency in the First Trimester (between 11-13+6 weeks) and the results are available less than one week after your appointment. The advantage of this testing is that results are available early. Therefore, you can have early ressurance if your results are screen negative. If your results are screen positive, early information allows extra time for decision making and the availability of a timely diagnostic test (chorionic villus sampling or amniocentesis).
2. Nuchal Translucency:
Alternatively, some individuals choose to have SIPS through the Provincial Screening Program. If you choose this option, you can get a nuchal translucency done at Genesis. The Provincial Screening Program will combine the results from the nuchal translucency at Genesis with SIPS through the Province, giving an IPS result. This option has a reduced fee compared to First Trimester Screening at Genesis, as no bloodwork will be done through Genesis.
First Trimester Screening at Genesis and IPS (nuchal translucency at Genesis with SIPS through the province) provide equivalent high detection rates for Down syndrome. The only downside with first trimester screening is that a slightly increased number of normal pregnancies will have screen positive results. However, most people choose first trimester screening for the benefit of early information.
How do I get my results?
The results of your screening will be discussed with you either by telephone or in person by Dr. Jason Hitkari. If you are “screen positive”, counseling will be offered to help review the results and discuss the options.
How do I arrange to have the test done?
You may be referred by your health-care provider (midwife, family doctor or obstetrician), or you may refer yourself by calling (604) 879-3038 to book a time for the testing.
When is Nuchal Screening done?
It is important to note that testing can only be done between 11 and 14 weeks gestation. Booking should be done as early as possible. If you are close to 14 weeks, we will do our best to fit you in.
Who will perform the testing?
Dr. Jason Hitkari is an Obstetrician/Gynecologist and Reproductive Endocrinology subspecialist who is licensed by the Fetal Medicine Foundation to perform NT measurements. He or the genetic counselor will contact you directly with the results of your testing and provide a copy to your health care provider.
What will my visit to Genesis be like?
We pride ourselves on being professional, courteous, and friendly. When you arrive at our facility, you will be asked to fill out a short history form about your medical and pregnancy history. You will then have an ultrasound done by Dr. Hitkari to obtain the NT measurement, confirm the pregnancy dates, and look at fetal anatomy. Once this is done, a finger-prick blood sample will be taken. The whole visit will take approximately one hour. Analysis of the blood work will take 2-3 days. Once those results are available, you and your health care provider will be notified of the results.
Is that all the testing that I will need during pregnancy?
It is very important to understand that routine prenatal care should continue as scheduled by your midwife, family doctor, or obstetrician. This will include another routine and detailed ultrasound between 18 and 20 weeks gestation. In addition, a blood test during the second trimester measuring alpha-fetoprotein should be completed to screen for neural tube defects. This will be arranged by the health care provider looking after you during the pregnancy. Any obstetric complications that arise during your pregnancy will be managed by your health care provider.