Nama lain bagi DNA Test ni adalah Chrionic Villus Sampling (CVS) di mana kebiasaannya DNA di ambil semasa kandungan berusia 11 - 13 minggu menggunakan jarum suntikan. Uishh mcm negeri jer baca dan ianya boleh menyebabkan risiko keguguran juga. CVS pada dasarnya adalah untuk melihat samada kandungan itu tidak normal seperti Down's Syndrome. Tetapi untuk aku lebih kepada untuk melihat samada darah kami suami isteri sepadan atau ada di antara kami yg membawa gen2 jahat yg menyebabkan kandunganku tidak dtp membesar atau terbantut semasa di awal first trimester.
Tapi oleh kerana teknologi semakin maju, DNA test ni da boleh buat menggunakan darah suami dan isteri juga. So tak perlu risikokan kandungan kan, elok la tu..
Nak tahu lebih lanjut pasal CVS ni bleh baca ni:
What is CVS?
Chorionic villus sampling (CVS) is a very accurate antenatal test that detects chromosomal abnormalities such as Down's syndrome. It's a diagnostic test, which means that it can tell you with almost complete certainty whether or not your baby has got a particular condition.
How is the test performed?
Your obstetrician should give you the opportunity to discuss the pros and cons of the test before you have it. Make a list of all the questions you want to ask; it's easy to forget them when you get to the hospital.
Your bladder needs to be full for the procedure, so you will be asked to drink plenty of water beforehand. You'll be asked to lie down for the test.
Ultrasound is used throughout the procedure, first to confirm how many weeks pregnant you are, and to locate the placenta. The ultrasound examination might be uncomfortable when the doctor presses down on your tummy with a small, hand-held transducer. However, you'll be able to see your baby on the screen which is a bonus!
Depending on your stage of pregnancy, the position of your placenta, or on personal preference, your doctor will choose one of the following methods:
• transvaginal CVS - usually carried out between 11 and 13 weeks of pregnancy, via the cervix. Your doctor will carefully insert fine forceps or a small tube through yourvagina and cervix to reach the placenta.
• transabdominal CVS - usually carried out after 13 weeks, through the abdomen. You may be given a local anaesthetic to numb the wall of your abdomen before a needle is inserted through your abdomen into your uterus to the placenta.
Ultrasound is used continuously to guide insertion of the instrument, whichever method is used. Your doctor will then extract a fragment of chorionic villi, which are tiny finger-like projections on the placenta. The cells taken from the placenta are full of genetic information that can be analysed to reveal the chromosomal make-up and the sex of your baby. If you don't want to know whether you're having a boy or girl, say so.
After the procedure, your baby will be checked using ultrasound. If your blood group is rhesus negative (RhD negative), you'll be offered an injection of anti-D immunoglobin to prevent any problems if your baby's blood is rhesus positive. Find out more in our article on rhesus status.
Your bladder needs to be full for the procedure, so you will be asked to drink plenty of water beforehand. You'll be asked to lie down for the test.
Ultrasound is used throughout the procedure, first to confirm how many weeks pregnant you are, and to locate the placenta. The ultrasound examination might be uncomfortable when the doctor presses down on your tummy with a small, hand-held transducer. However, you'll be able to see your baby on the screen which is a bonus!
Depending on your stage of pregnancy, the position of your placenta, or on personal preference, your doctor will choose one of the following methods:
• transvaginal CVS - usually carried out between 11 and 13 weeks of pregnancy, via the cervix. Your doctor will carefully insert fine forceps or a small tube through yourvagina and cervix to reach the placenta.
• transabdominal CVS - usually carried out after 13 weeks, through the abdomen. You may be given a local anaesthetic to numb the wall of your abdomen before a needle is inserted through your abdomen into your uterus to the placenta.
Ultrasound is used continuously to guide insertion of the instrument, whichever method is used. Your doctor will then extract a fragment of chorionic villi, which are tiny finger-like projections on the placenta. The cells taken from the placenta are full of genetic information that can be analysed to reveal the chromosomal make-up and the sex of your baby. If you don't want to know whether you're having a boy or girl, say so.
After the procedure, your baby will be checked using ultrasound. If your blood group is rhesus negative (RhD negative), you'll be offered an injection of anti-D immunoglobin to prevent any problems if your baby's blood is rhesus positive. Find out more in our article on rhesus status.
Will it hurt?
Many women find the procedure uncomfortable rather than painful, and describe feeling period-type pains. However, it's over relatively quickly. The test lasts no longer than half an hour from start to finish and actually taking the sample is only a matter of a few minutes.
Women who have a transvaginal CVS say it feels rather like having a smear test. Women who have a transabdominal CVS sometimes report a sore tummy afterwards.
Women who have a transvaginal CVS say it feels rather like having a smear test. Women who have a transabdominal CVS sometimes report a sore tummy afterwards.
What happens after the test?
Having a CVS or amniocentesis or any other antenatal test can be physically and emotionally exhausting. Your doctor will advise you to rest after your CVS, if you feel like it. It's a good idea to have someone with you, to drive you home or travel with you if you're using public transport. Spend the rest of the day relaxing if you can, watching TV, reading or dozing.
You might have some cramping in your tummy and a slight loss of blood from thevagina in the first 24 hours after the test. These are nearly always normal side effects, but let your doctor know.
If you notice bleeding or clear fluid leaking from your vagina, or if you have contractions or feel shivery (like you're going down with flu) contact your doctor immediately.
You might have some cramping in your tummy and a slight loss of blood from thevagina in the first 24 hours after the test. These are nearly always normal side effects, but let your doctor know.
If you notice bleeding or clear fluid leaking from your vagina, or if you have contractions or feel shivery (like you're going down with flu) contact your doctor immediately.
Why might I choose to have a CVS rather than an amniocentesis?
The main advantage of CVS over amniocentesis is that it can be performed earlier; usually between 10 and 13 weeks of pregnancy, compared to amniocentesis which is recommended from 15 weeks of pregnancy.
CVS appeals particularly to women who want to know as soon as possible if their baby has a disorder. CVS will be offered to you if:
• a blood test, a nuchal translucency scan or a combination of the two has shown that your baby is at higher risk than usual of having chromosomal problems.
• you are over 35 and haven't had screening for Down's syndrome already.
• you have one or more relatives with a genetic disorder.
• you or your husband is at greater risk of having a child with an inheritable condition, such as thalassaemia.
• you have had a previous pregnancy affected by a genetic abnormality.
CVS appeals particularly to women who want to know as soon as possible if their baby has a disorder. CVS will be offered to you if:
• a blood test, a nuchal translucency scan or a combination of the two has shown that your baby is at higher risk than usual of having chromosomal problems.
• you are over 35 and haven't had screening for Down's syndrome already.
• you have one or more relatives with a genetic disorder.
• you or your husband is at greater risk of having a child with an inheritable condition, such as thalassaemia.
• you have had a previous pregnancy affected by a genetic abnormality.
Is CVS more likely than amniocentesis to cause a miscarriage?
Yes, but only very slightly. About two in every 100 women miscarry as a direct result of CVS compared with about one in every 100 women after amniocentesis.
Are there any other risks?
In the past, CVS was associated with babies born with limb defects, but this link was only found when the test was carried out before 10 weeks of pregnancy. It has since been found that such problems are extremely rare and may not be connected to CVS. Nevertheless, CVS is done only after 10 weeks because of the possible risk.
If you have HIV, there is an increased risk of transmission of the virus to your baby during CVS. For this reason, it is best avoided. If you still want to go ahead then you'll need treatment with HAART (highly active antiretroviral therapy) during the procedure to reduce the risk of transmission to your baby.
If you have hepatitis B or hepatitis C, there is no evidence that transmission of the disease to your baby is increased by CVS.
If you have HIV, there is an increased risk of transmission of the virus to your baby during CVS. For this reason, it is best avoided. If you still want to go ahead then you'll need treatment with HAART (highly active antiretroviral therapy) during the procedure to reduce the risk of transmission to your baby.
If you have hepatitis B or hepatitis C, there is no evidence that transmission of the disease to your baby is increased by CVS.
If the risks of CVS and amniocentesis are about equal, why doesn't everyone have CVS?
You might not have discovered that you were pregnant until later in pregnancy when an amniocentesis is the usual test offered, or you might have experienced a previous first trimester miscarriage and be unwilling to run that risk again.
Deciding which antenatal test to have (or whether to have any at all) is a very personal decision. You might choose CVS if you have a very specific reason to believe that there might be something wrong with your baby and you want to find out as soon as possible. On the other hand, if your only reason for concern is your age, you might choose to wait for an amniocentesis and minimise the risk of miscarriage.
Deciding which antenatal test to have (or whether to have any at all) is a very personal decision. You might choose CVS if you have a very specific reason to believe that there might be something wrong with your baby and you want to find out as soon as possible. On the other hand, if your only reason for concern is your age, you might choose to wait for an amniocentesis and minimise the risk of miscarriage.
Will I get the results straight away?
You might have to wait two to three weeks for the results of the CVS. The sample has to be sent away to a lab to be cultured and the chromosomes fully counted and examined (karyotyped).
A new rapid test has been developed which can give results for some chromosome problems after about three working days. Your doctor will be able to tell you if it is available in your hospital or centre. For more information, visit www.amniopcr.com.
Even if you opt for the rapid test and it comes back clear, the results from the full karyotype may indicate a problem that wasn't checked for as part of the quick test so you'll still have a long wait.
Very occasionally, an abnormality known as mosaicism shows up on the CVS test when it doesn't actually exist in the baby. Mosaicism means that some cells have a chromosomal abnormality while others are normal. If you receive this diagnosis, your doctor will discuss with you whether you would like to have an amniocentesis to confirm the result.
This is probably going to be a very difficult time. It might help to keep busy, and give yourself several treats to help pass the time as easily as possible.
A new rapid test has been developed which can give results for some chromosome problems after about three working days. Your doctor will be able to tell you if it is available in your hospital or centre. For more information, visit www.amniopcr.com.
Even if you opt for the rapid test and it comes back clear, the results from the full karyotype may indicate a problem that wasn't checked for as part of the quick test so you'll still have a long wait.
Very occasionally, an abnormality known as mosaicism shows up on the CVS test when it doesn't actually exist in the baby. Mosaicism means that some cells have a chromosomal abnormality while others are normal. If you receive this diagnosis, your doctor will discuss with you whether you would like to have an amniocentesis to confirm the result.
This is probably going to be a very difficult time. It might help to keep busy, and give yourself several treats to help pass the time as easily as possible.
Sumber: http://www.babycenter.com.my/pregnancy/antenatalhealth/testsandcare/cvs/
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