CVS stands for chorionic villus sampling. Not made available on a regular basis, the process is often used to determine whether a fetus has a chromosomal abnormality like Down Syndrome.
Women who have a higher likelihood of having a baby with a disease are typically offered CVS. The procedure is most secure when performed after 10 weeks of pregnancy.
This blog explains everything about CVS and what you should know if you are considering having this procedure throughout your pregnancy.
The information provided here is intended to assist you and your healthcare team in making the best decisions regarding your care. Please consult your healthcare professional if you require any additional information on this subject.
What is CVS?
CVS is a diagnostic test used during pregnancy. It is most usually used to screen the baby’s chromosomes for specific illnesses such as Edward syndrome or Down syndrome, as well as a few other genetic abnormalities.
Although it can only reveal a small number of anatomical details, an ultrasound scan of the fetal anatomy is also carried out at the same time as CVS.
CVS in Pregnancy: Who needs CVS?
Some of the common reasons to have chorionic villus sampling in pregnancy are;
- To evaluate the fetal chromosomes in high-risk pregnancies during prenatal screening
- If the woman has had a previous pregnancy with a chromosomal abnormality, she should avoid having another one.
- If a known parental chromosome problem exists
- If an abnormality is discovered during an ultrasound scan early in pregnancy.
Is it important to do CVS? Factors to consider before deciding on CVS
Making the decision to have CVS is often stressful and difficult.
As a result, it is critical that you and your partner have thoroughly discussed the issues surrounding CVS among yourselves and with your doctor before undergoing the procedure.
Prior to the procedure, you should expect to discuss the following topics:
Is CVS early pregnancy test accurate?
Although no test is perfect, it should be reassuring to know that chorionic villus sampling is considered to be 99 percent accurate.
There is a small chance of a false-positive test with chorionic villus sampling, which occurs when the test is positive but no disease exists.
It’s also worth noting that chorionic villus sampling cannot detect all birth defects, including spina bifida and other neural tube defects.
Difference between NIPT and CVS
NIPT is an easy, safe, and non-invasive prenatal screening test that gives parents-to-be certainty that the genetic information they get about their unborn child is reliable.
The test analyses maternal blood for fetal DNA (of placental origin) using cutting-edge bioinformatics technologies.
Regardless of the risks, medical associations currently endorse the use of NIPT as the first line of screening for all pregnancies.
NIPT is more sensitive than CVS for detecting CPM involving the cytotrophoblast that is restricted to a (small) portion of the placenta. Let us learn the differences between the both in this section.
What are the risks associated with CVS?
There is a chance of miscarriage during every pregnancy.
A miscarriage may occasionally result from CVS owing to an infection or injury in the womb. About 2% more miscarriages occur overall as a result of CVS.
In other words, after 10 weeks, about 2 out of every 100 women who undergo CVS with ultrasound supervision may miscarry.
This will be discussed in detail by your healthcare provider prior to the procedure.
Less than 1 in 1000 women with CVS will experience a severe infection as a result of the operation.
Both skin contamination and needle puncturing the colon can result in infection, however, none of these scenarios is expected if normal CVS procedures are followed.
Additionally, contamination of the needle by the ultrasonic probe or gel can result in infection. Standard practices to reduce infection, such as the use of sterile gel, can lower these risks.
Regular CVS practitioners appear to be slightly more adept at obtaining enough placental tissue during the operation and may also experience a lower chance of miscarriage. At Jammi Scans, your procedure is as safe as we can make it.
Is CVS worth the risk?
One of the first things people worry about at CVS is the possibility of miscarriage. According to the NHS, one in every 50 or 100 women will miscarry after having CVS. This is slightly higher than the NHS estimate for an amniocentesis, which is closer to 1%.
It also claims that it is difficult to determine which miscarriages would have occurred regardless of CVS.
According to NHS’s recent research, only a small number of miscarriages occur as a direct result of the procedure. If you have a miscarriage, it will most likely happen within two weeks of the test.
CVS in Procedure
Discovering that you may require CVS during your pregnancy can be a very stressful time. You’re probably feeling very perplexed, and this is a great place to learn more about what’s involved and whether or not it’s something you want to pursue. The CVS procedure is as follows;
You can perform the test through your belly (transabdominal). Another option is to use your cervix (transcervical). Cramping is typical both during and after the CVS procedure.
Before the Test
You might experience anxiety or trepidation before the chorionic villus sampling procedure. That is typical. By learning as much as you can about the procedure beforehand, you might be able to at least partially reduce your anxiety.
Remember that the doctor and nurse who will assist you during this procedure are available to walk you through everything and respond to any questions you may have.
Whether you are having transabdominal CVS or transcervical CVS, the following is what to anticipate.
Pre-Test – Chorionic villus sampling full bladder
It’s possible that you’ll be told not to urinate the morning of the test. This is because the doctor may be able to guide the needle or catheter more easily when the bladder is full.
In either case, your doctor will discuss the procedure with you once you’ve arrived and checked in at the office. Then, you’ll have a short window of time to get ready.
Prior to the test, you will also receive an ultrasound. This process creates images on a screen by using sound waves and a computer.
You will have the privacy to put on a hospital gown or to completely undress, starting at the waist. You will be given a sheet or paper drape to cover your lower body. If your feet are cold, you can keep your socks on.
A nurse will make you sit down at the exam table when you’re prepared. She will check your breathing, heart rate, and blood pressure. The doctor will enter the room to start the test at some point during this procedure or soon after.
Throughout the CVS test
Regardless of the type of test you’re having, the initial step will be an ultrasound because both transabdominal and transcervical (explained below), the CVS rely on ultrasound to help the practitioner guide the needle.
In order to establish that you are between 10 and 13 weeks pregnant and that it is a safe time to perform CVS testing, the doctor will double-check the gestational age of the unborn child.
In order to precisely guide the needle, the doctor can also detect the placenta using ultrasound. Your abdomen will be covered in a cold, transparent, water-based gel for this operation to make it easier for the hand-held transducer to glide along your skin while picking up sound waves that create an image of the interior of your uterus.
Depending on how the ultrasound monitor is positioned in relation to the exam table, you might be able to see and hear the baby’s heartbeat there.
Transabdominal CVS:
Your abdomen will first be cleaned with an antiseptic solution to help avoid infection because a foreign object, i.e, a needle will be inserted into your body. To numb your skin, a local anesthetic may also be administered to you. In that case, you can experience a needle stick and a momentary stinging sensation.
Your doctor will insert a hollow needle into your lower abdomen. The needle used for CVS is somewhat longer and roughly the same thickness as the one used to take blood from your arm.
The doctor will carefully slide the needle out and carefully check the sample to ensure that enough cells were removed after the cells have been collected.
Rarely will the procedure need to be done again because the initial sample didn’t produce enough cells. You can be advised to have an amniocentesis later in your pregnancy if a transabdominal CVS needs to be performed three times and there are still insufficient cells.
The excess ultrasound gel on your abdomen will be removed after the test is finished, and the doctor or nurse may apply a little bandage to the spot where the needle was entered.
Transcervical CVS:
This is similar to a pap smear-like procedure. Your bottom should be near the end of the table, your knees bent, and your feet firmly planted in the stirrups.
A speculum, which the doctor will implant into your vagina, is a device that holds the walls of your vagina apart while allowing the doctor easy access to your cervix. It can be built from metal or plastic.
If the speculum is made of metal, it might also be warmed up in order to make it slip in more readily. As the speculum is adjusted, you’ll feel some pressure and hear a clicking sound.
If it hurts, say something because a smaller speculum could be required. It shouldn’t.
Your vagina and cervix will be cleaned with an antiseptic while the speculum is in place to help avoid infection.
The chorionic villi will then be reached by guiding a very thin catheter into your cervix. The catheter will be used to suck cells into a syringe. At this moment, you can experience a pinch or cramping. Again, pain shouldn’t be an issue.
You will be given a wipe to remove the ultrasound gel from your abdomen and any remaining lubricant in or around your vagina.
Post-Test
The sample will be transferred to a specialized genetics lab after being taken. Your vital indicators will be rechecked and the baby’s heart rate will be tracked for the following hour or so.
As soon as your doctor determines that you and the baby are both in stable condition, you are free to get dressed and go.
After the test
It can be suggested that you return home and relax for at least a day. Avoid any intense activity. Unless your doctor instructs you otherwise, you also shouldn’t douche or engage in sexual activity for two weeks following CVS testing.
A few days following your CVS, your doctor might want to perform a follow-up ultrasound to check sure everything appears to be in order.
How long does the CVS procedure take?
The entire test is completed in less than 30 minutes. The actual extraction only takes a few minutes.
CVS complications – Chorionic villus sampling side effects
After your CVS, you can suffer some spotting or discomfort. A little pad can be used to stop bleeding. You might also take an over-the-counter painkiller if your doctor approves. Try using a heating pad or a warm bath to relieve soreness if you don’t want to take medication.
Although there is little chance that a CVS test will have any significant adverse effects, there are certain indicators that anything could go wrong. Inform your healthcare provider as soon as possible if you notice any of these signs:
- Bleeding from the cervix
- Bleeding or fluid discharge from the needle’s insertion site (if you had a transabdominal CVS)
- A leak in the amniotic sac
- A temperature or chills
- Significant stomach discomfort or uterine contractions (cramping)
CVS equipment
For transabdominal CVS, generally, a needle does the job. It is inserted through your tummy as an invasive process.
For transcervical CVS, small forceps or smooth metal instruments similar to tongs are used to insert through the neck of the womb.
Is chorionic villus sampling dangerous?
Due to the fact that CVS is performed in the early stages of pregnancy, there may be a modest increase in miscarriage risk compared to amniocentesis. This has one of the main reasons why CVS is considered to be dangerous.
Some other reason why CVS is feared is its chances of infection. Rare incidences of finger or toe abnormalities in infants have been documented, particularly when CVS was performed before 9 weeks.
This danger does not appear to be connected to the doctor’s training or the method of the test. The earliest recommended period for this test is typically 10 weeks due to this potential risk.
With twins, CVS can be a little more challenging than with a single baby. Inform your healthcare provider of the dangers. Make certain the physician has much expertise performing CVS on twins.
Is CVS painful?
The majority of women report that CVS, whether transabdominal or transcervical, causes discomfort rather than agony, somewhat akin to period pain. According to some women, the transcervical procedure is similar to getting a cervical smear. Women express their anxiety as well.
You should seek medical care right away if you suffer any unexpected symptoms right away following the test, such as feeling shivery, as if you have the flu, fluid loss, blood, or contractions.
How much bleeding is normal after CVS?
“Bleeding” could just be spotting for about 24 to 48 hours, which may need one or two sanitary pads in a day. Sometimes you may not have bleeding at all, which is just normal.
CVS Report
The time it takes to receive the results of a CVS test might range from a few days to as many as two weeks. To discuss these, your doctor will give you a call.
If the results of your CVS test are normal, your child has no chromosomal abnormalities or indicators of genetic diseases.
While it’s crucial to remember that no test is flawless, the fact that a chorionic villus sample is thought to be 99 percent accurate should give you some comfort.
A baby can have a complete life by managing their Down syndrome in a variety of ways. Unfortunately, there are other disorders that can be deadly or cause severe birth abnormalities.
There are a number of phrases that frequently appear in the results of prenatal testing, despite the fact that there are hundreds of ailments connected to genetic or chromosomal issues. Here are some typical examples:
Trisomy: When a chromosomal pair has an additional chromosome, the condition is referred to as trisomy. For instance, trisomy 21, also referred to as Down syndrome, develops when there are three chromosomes 21 instead of two. Similar to trisomy 13, which results in an additional chromosome 13, Patau syndrome is also caused by trisomy 13.
Translocation: Translocation is the joining of two chromosomes that are not identical. Emanuel syndrome is an example of a condition brought on by a translocation mutation. Each cell in this condition contains excess genetic information from chromosomes 11 and 22, which results in traits like an unusually small head, a short lower jaw, and malformed ears.
Mosaicism: Only a few cells will exhibit mosaicism, in which an extra copy of a chromosome is present.
Fractured chromosomes: Chromosomes that are broken up in cell culture are referred to as having “fractured chromosomes,” which may have health repercussions for the unborn child as an adult.
You must discuss your options with your doctor or genetic counselor as soon as your CVS test results are known so that you may make an educated choice.
For instance, you should research potential therapies for the disease your child has either in utero or after he or she is born. It’s crucial to know what specific requirements to prepare for and whether there’s a danger the pregnancy won’t be viable. You might also be interested in learning more about your options for carrying the pregnancy to term.
What if CVS is positive?
A positive result indicates that the test identified a genetic anomaly in you. In some situations, along with your own physician, you will have the opportunity to speak with an obstetrical geneticist and a genetic counselor from our Jammi Scans team about the diagnosis and your alternatives.
What if the CVS test is negative?
If the results are anomalous, we will go in-depth with you about them. There is typically no therapy or cure for diseases.
You must decide what is best for both you and the infant. This could be done in one of two ways: either continue with the pregnancy while using the knowledge you have received to help with labor preparation and postpartum care or end this pregnancy.
Before choosing to have CVS, it is good to discuss all your options with your doctor or midwife. Discussing your options with a pediatrician and a consulting geneticist or genetic nurse counselor should be possible.
Some women who made an educated decision to terminate their pregnancy choose to speak with a counselor about their experience.
CVS advantages – Benefits of CVS in Pregnancy
The main benefit of CVS are;
- It is accurate, and well enough to make crucial healthcare decisions
- It is done earlier, so helps in making better decisions
- The test gives critical information about having a baby with a genetic disorder and other major problems. The results may help you in having special treatments planned for your baby immediately after birth. Alternatively, you can even decide to terminate the pregnancy.
- CVS is the preferred approach since it facilitates the supply of large volumes of DNA to the molecular laboratory to assist in an accurate result.
Concluding notes from Jammi Scans
CVS testing or Chorionic villus sampling done during pregnancy helps understand if your unborn fetus has certain genetic complications. If you agree to do the test, it will be carried out between 10 to 13 weeks of pregnancy.
The test is completely safe and accurate and causes very less discomfort when done by professionals like those in the Jammi Scans.
It’s crucial to have adequate time and to feel supported in your choice when deciding whether to undergo CVS. Give yourself enough time to discuss your alternatives and make any necessary requests for more information.
You have the final say in the matter. Only you may decide how much you value learning about a disorder early on compared to the minor possibility that the operation could result in miscarrying a child who may or may not have a disorder.
Before the procedure is done, you will be required to sign a consent form if you choose to have CVS.
If you are unsure about your decision, call our team for a one-to-one discussion. Our expert fetal medicine expert who is also a gynecologist-obstetrician can help you figure out what is best for you and your unborn.
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