Chorionic Villus Sampling (CVS) Test:
The CVS, chorionic villus sampling, test is used to identify the odds of the baby having chromosome abnormalities and/ or other inherited disorders. The test is offered to woman that are between 10 and 13 weeks pregnant. A sample of the chorionic villi cells from the placenta are collected and tested to determine the odds of the baby having any abnormalities. The sample can be collected either vaginally or by needle going through the abdomen. According to the American Pregnancy Association the procedure is safe but there is a risk of miscarriage; " Miscarriage is the primary risk related to CVS occurring 1 out of every 100 procedures."
Amniocentesis Test:
The amniocentesis or amniotic fluid test (AFT), is another option to test for the potential of abnormalities and/ or defects in the baby. This test can be done between weeks 16 and 22 of pregnancy. The procedure for this test is to inject a needle into amniotic sac through the abdomen and uterus after a local anesthetic is given to the mother and extract some of the amniotic fluid for testing. Unlike the CVS test, the AFT can also screen for neural tube defects.
Some risks of amniocentesis testing are miscarriage, needle injury to the baby if the needle sticks them, and leaking amniotic fluid. The risk of miscarriage from this test is lower than that of CVS testing; estimated that a miscarriage related to AFT occures between 1 out of every 300 to 1 out of every 500 procedures, as per the Mayo Clinic website.
New testing
The two above tests are the most common based on my findings in books, magazines, chat boards, and online searches. These have been the norm for at least the past decade if not longer. Lucky for me, I did not do either of these tests as neither option seemed pleasant. Instead my doctor told me that as of last year (so 2013) a blood test is being used to test for chromosome abnormalities. I hate having blood drawn but it's a less invasive method without any known risk of miscarriage and the newest technology. Plus I love my obstetrician and trust his judgement. The new blood test to screen for chromosome deficiencies and baby sex is offered by two companies. The one that I did is called the Panorama test.
Panorama Test:
The Panorama test is a simple non invasive blood test that is used to determine the babies odds of abnormalities and defects. During pregnancy some of the DNA of the baby crosses into the mother's blood stream. So a number of vials of blood are drawn (I think they took about 9 vials!) and then a lab pulls DNA information from the blood, dividing the DNA of the fetus from the DNA of the mother and then evaluating the
Most people have 23 pairs of chromosomes, with a total of 46 (2 copies of each). The Panorama tests screens to check the chromosomes to see if there are any extra chromosomes or only one when there should be a pair. Three of the chromosomal abnormalities that Panorama screens for are trisomy 21, trisomy 18, and trisomy 13, which result in Down syndrome, Edwards syndrome and Patau Syndrome, respectively. All of these syndromes are a result of having a third chromosome (either partial or full) rather than the standard pair. Other birth defects that the test screens for are monosomy X, triple X syndrome, and Jacob syndrome.
The Panorama test also determines the sex of the baby. Along with screening for various chromosome defects the Panorama test determines if the baby is a boy or a girl. By seeing if the sex chromosomes are XX (girl) or XY (boy) the sex of the baby is determined. This is an added plus because it's often too difficult to get a good ultrasound view early in the pregnancy to determine the sex of the baby.
Although the Panorama test website states that the test can be done as early at 9 weeks of pregnancy, my doctor scheduled me to come in for the blood test at 12 weeks. They then send away the blood samples to the lab and it takes about 2 weeks to get the results (according to the website it's only about a week but I'm sure most doctor offices add in time for specimen shipment and results to come back). I got a call exactly 2 weeks later- but the results came back inconclusive.
My doctor explained that the inconclusive results were not an indication that anything was wrong. What happened was that there was not enough fetal DNA extracted from my blood to attain results so I had do go in again to be retested with a second blood test. DNA was also taken from the father, by getting a cheek swap. This is optional with the Panorama test so it was not done the first time I had it done.
The second test came back another 2 weeks later without an issue. The way the results work is that based on the analysis of the fetal DNA you find out if you are at low or high risk of having a baby with abnormalities. The results list of the risk of each condition (such as trisomy 21, trisomy 18, etc) and if the baby is at low or high risk. The test also breaks down the odds of the condition based on the mother's age.
For example my results listed:
Trisomy 21 (Down Syndrome) risk based on my age is 1/266 and based on the blood work- my risk is less than 1/10000 resulting in Low Risk.
The doctor can go over the results and if any of the results come back high risk further testing can be done. In my case everything came back as low risk so the odds of my baby having any birth defects or abnormalities is very low. Great news! We also found out the sex of the baby but I'm saving that for another post.
Hope this was informative for some and if you're here just to follow my pregnancy and progress hope this wasn't too boring for you- thanks everyone!
The two above tests are the most common based on my findings in books, magazines, chat boards, and online searches. These have been the norm for at least the past decade if not longer. Lucky for me, I did not do either of these tests as neither option seemed pleasant. Instead my doctor told me that as of last year (so 2013) a blood test is being used to test for chromosome abnormalities. I hate having blood drawn but it's a less invasive method without any known risk of miscarriage and the newest technology. Plus I love my obstetrician and trust his judgement. The new blood test to screen for chromosome deficiencies and baby sex is offered by two companies. The one that I did is called the Panorama test.
Panorama Test:
The Panorama test is a simple non invasive blood test that is used to determine the babies odds of abnormalities and defects. During pregnancy some of the DNA of the baby crosses into the mother's blood stream. So a number of vials of blood are drawn (I think they took about 9 vials!) and then a lab pulls DNA information from the blood, dividing the DNA of the fetus from the DNA of the mother and then evaluating the
Most people have 23 pairs of chromosomes, with a total of 46 (2 copies of each). The Panorama tests screens to check the chromosomes to see if there are any extra chromosomes or only one when there should be a pair. Three of the chromosomal abnormalities that Panorama screens for are trisomy 21, trisomy 18, and trisomy 13, which result in Down syndrome, Edwards syndrome and Patau Syndrome, respectively. All of these syndromes are a result of having a third chromosome (either partial or full) rather than the standard pair. Other birth defects that the test screens for are monosomy X, triple X syndrome, and Jacob syndrome.
The Panorama test also determines the sex of the baby. Along with screening for various chromosome defects the Panorama test determines if the baby is a boy or a girl. By seeing if the sex chromosomes are XX (girl) or XY (boy) the sex of the baby is determined. This is an added plus because it's often too difficult to get a good ultrasound view early in the pregnancy to determine the sex of the baby.
Although the Panorama test website states that the test can be done as early at 9 weeks of pregnancy, my doctor scheduled me to come in for the blood test at 12 weeks. They then send away the blood samples to the lab and it takes about 2 weeks to get the results (according to the website it's only about a week but I'm sure most doctor offices add in time for specimen shipment and results to come back). I got a call exactly 2 weeks later- but the results came back inconclusive.
My doctor explained that the inconclusive results were not an indication that anything was wrong. What happened was that there was not enough fetal DNA extracted from my blood to attain results so I had do go in again to be retested with a second blood test. DNA was also taken from the father, by getting a cheek swap. This is optional with the Panorama test so it was not done the first time I had it done.
The second test came back another 2 weeks later without an issue. The way the results work is that based on the analysis of the fetal DNA you find out if you are at low or high risk of having a baby with abnormalities. The results list of the risk of each condition (such as trisomy 21, trisomy 18, etc) and if the baby is at low or high risk. The test also breaks down the odds of the condition based on the mother's age.
For example my results listed:
Trisomy 21 (Down Syndrome) risk based on my age is 1/266 and based on the blood work- my risk is less than 1/10000 resulting in Low Risk.
The doctor can go over the results and if any of the results come back high risk further testing can be done. In my case everything came back as low risk so the odds of my baby having any birth defects or abnormalities is very low. Great news! We also found out the sex of the baby but I'm saving that for another post.
Hope this was informative for some and if you're here just to follow my pregnancy and progress hope this wasn't too boring for you- thanks everyone!
Good news to read!! It's also a lot of great information! I can't wait to find out if it's a boy or a girl!! What a nerve-racking four weeks for you though!
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