Natera’s Miscarriage Test
When you need answers, Natera can help.
If you have had a miscarriage, you may have questions about why you lost your pregnancy, and what to do next. Pregnancy loss, or miscarriage, happens more often than you might think. In fact, it happens in up to 25% of all pregnancies. The chance of having a miscarriage goes up with age – from close to 10% for women in their 20s to nearly 50% for women in their early to mid-40s.
Fertility and Miscarriage Rates as a Function of Maternal Age
Adapted from Menken et al. and Anderson et al.
More than half of first-trimester miscarriages are caused by a chromosome abnormality. Most pregnancies that involve chromosome abnormalities end in miscarriage during the first 12 weeks. If you have experienced pregnancy loss due to a chromosome abnormality, it is still possible to have a healthy child in the future.
Benefits of Natera's Miscarriage Test
- Fast. Results within 5 business days of receiving the sample.
- Easy. Natera will provide a collection kit that your doctor can use to collect and mail the sample to Natera for testing. If you choose, Natera will bill your insurance provider.
- Reliable. Results returned >99% of the time, more often than traditional miscarriage tests.
Dr. Pellegrini Does Testing on Preserved Miscarriage Samples
"The ability to test pregnancy losses preserved in paraffin has been immensely useful for my infertility practice, especially for patients having repeat pregnancy losses. Not only have we gone back in time to de novo test previous losses, but we have also been able to retest cases in which fresh POC samples returned as normal female or maternal cell contamination (MCC) results using traditional cytogenetics karyotyping. This testing has provided valuable results for a number of my patients who previously had no answer for why their losses occurred. This new technology should replace traditional POC cell culture karyotyping in my opinion."Vincent A. Pellegrini, MD, FACOG, Women's Clinic, Ltd., Reading PA
The Science Behind the Test
Miscarriage testing from Natera gives you the best chance of finding the answers you need.
- Whole extra or missing chromosomes (aneuploidy)
- A complete extra set of chromosomes (triploidy)
- Pieces of chromosomes that are extra or missing (deletions and duplications)
- Two copies of a chromosome from the same parent (uniparental disomy)
- Maternal cell contamination (MCC)
- Parental origin of the abnormality
Is Miscarriage Testing Right for Me?
Miscarriage chromosome testing can be helpful if you:
- Want to better understand why you had a miscarriage
- Have had more than one miscarriage
- Have had a child or previous pregnancy with a chromosome abnormality
The choice to have chromosome testing after a miscarriage is very personal. Although not all doctors will recommend chromosome testing for a pregnancy loss, it can be helpful for couples who have a miscarriage and want to know the cause.
If a chromosome abnormality is found, it can lower the number of other medical tests you might need to have in order to determine the cause of the pregnancy loss. Knowing the reason for a miscarriage may help you cope with the loss and start the emotional healing sooner.
Chromosome testing can help answer the questions that often come up after a miscarriage including “Why did this happen?” and “Will it happen again?”
If a cause of your miscarriage is found, it can prevent the need for other costly and time-consuming medical tests. Chromosome miscarriage testing can be helpful for patients with more than one miscarriage. It can give clues to a reason for the miscarriage or rule out chromosome problems as the cause of the miscarriage.
How Do I Get Natera's Testing?
Steps for ordering Natera’s test:
- Talk with your doctor about testing your miscarriage sample
- Ask your doctor for Natera testing
- Collect miscarriage sample and blood sample at your doctor’s office
- Ship to Natera’s lab; results available in 5 business days
- Discuss the results with your doctor.
Contact Natera at 1-650-249-9090 for more information.
Frequently Asked Questions
What causes a miscarriage?
Up to 25% of all pregnancies end in miscarriage. There are many reasons why a miscarriage can happen. The most common cause is a chromosome abnormality. Chromosome abnormalities cause over half of all miscarriages. Most miscarriages due to chromosome involve a whole extra or missing chromosome.
Chromosome abnormalities prevent a baby from developing normally. They can cause a pregnancy to miscarry, or cause a baby to have birth defects or intellectual disability. In fact, more than 90% of embryos that have a chromosome abnormality will either not result in a pregnancy or will end in a miscarriage early in pregnancy. Most times a chromosome abnormality happens by chance. It is not caused by anything that either of the parents did before or during the pregnancy. Most chromosome abnormalities found in miscarriages are not inherited. Usually the chance of a chromosome problem in another pregnancy is low. In a small number of cases a miscarriage is caused by another type of genetic problem.
What is miscarriage chromosome testing?
Chromosome miscarriage testing looks at fetal tissue (also called products of conception or POC) after a miscarriage to find out if a chromosome abnormality was the cause of the loss.
When can miscarriage chromosome testing be done?
Chromosome testing is usually done after a D&C procedure or after home collection of miscarriage tissue or POC tissue.
Testing can be done on losses as early as 6 weeks. Natera may also be able to do testing on prior miscarriages if the tissue has been saved in paraffin. This type of testing may be helpful to patients who have had more than one pregnancy loss. Check with your doctor to see if a sample from a prior miscarriage has been saved.
How can miscarriage testing help?
Knowing the reason for a miscarriage can help you start the emotional healing process. You may have questions about why the miscarriage happened, and if you could have another miscarriage. Miscarriage testing may give you answers to your questions. If a chromosome abnormality is found, it may mean that you do not need more medical tests. This can help lower stress about medical visits and lower your medical costs.
Understanding the Results
What does it mean if a miscarriage is found to be due to a chromosome abnormality?
If a chromosome abnormality is found, you may not need to have other testing to find out the cause of the miscarriage.
Most chromosome abnormalities found in miscarriage tests are not inherited. However, sometimes a result can alert your doctor to look for an inherited genetic or chromosome problem in your family. Inherited chromosome abnormalities make the chance of another miscarriage higher. One example is a balanced translocation.
What if a miscarriage is not due to a chromosome abnormality?
If the cause of miscarriage is unknown, your doctor may recommend more tests to look for other causes of miscarriage.
What is maternal cell contamination?
Sometimes when testing miscarriage tissue the tissue studied is from the mother rather than the fetus. This is referred to as maternal cell contamination (MCC).
Normal female results after miscarriage testing can be from either the fetus or the mother. With other types of miscarriages tests, it is not possible to know if a normal female result is from the mother or the fetus which gives no information about why the miscarriage happened. It is like not having had testing at all. Natera’s miscarriage testing is able to tell you if a normal female result is from the mother, also called maternal cell contamination, or the fetus.
Often your doctor or the laboratory will sort and separate the miscarriage tissue in order to find fetal tissue for testing. Fetal tissue usually makes up less than 1% of the tissue passed during a miscarriage. Even with tissue sorting, there are times when no fetal tissue can be found in a miscarriage sample. Some studies have found that more than half of normal female chromosome results from miscarriage samples are due to MCC.
What happens if I get an MCC result?
MCC happens with miscarriage testing at all laboratories, no matter what type of testing type is done. At Natera we sort all tissue samples to look for fetal tissue, using a method that is known to reduce the chance of MCC.
No matter how carefully a sample is sorted, the chance of an MCC result is about 10-20%. When MCC is detected, Natera’s laboratory will test another part of the original sample. Sometimes this second try gives a fetal result instead of MCC.
Although it is disappointing to get an MCC result, the advantage to using a Natera’s Parental Support miscarriage testing is that the results are clear.
What can be detected by Natera's test?
Products of Conception (POC) testing is used to identify extra or missing chromosomes, significant chromosome deletions or duplications, and uniparental disomy (UPD) while ruling out maternal cell contamination in miscarriage samples. The information obtained from POC testing helps patients and physicians understand why a miscarriage happened and can help physicians with future medical management decisions.
What cannot be detected by Natera's test?
While Natera's molecular karyotype with Parental Support can find many chromosome abnormalities, it cannot detect balanced structural chromosome rearrangements, also called balanced translocations.
Balanced chromosome rearrangements or translocations are not likely to cause a miscarriage. Balanced chromosome rearrangements are reported as normal on the test results. Unbalanced chromosome rearrangements are often reported as aneuploidy, deletion, or duplication. There are other rare chromosome findings that cannot be detected.
How can different testing technologies affect test results?
All miscarriage testing is not created equal. Older tests like standard karyotyping need to grow the cells first in the laboratory (cell culture). This type of test takes up to 5 weeks and is not always successful. Up to 25% of the time cell culture fails, leading to no test results. In standard karyotyping there is no way to know if a normal female result is from the mother’s tissue or the fetal tissue, so you would not know if MCC happened.
Only Natera uses a SNP microarray combined with Parental Support technology to give highly accurate results more often and more quickly than standard karyotyping. Since no cell culture is needed, the chance for no results is less than 1% and results can be returned within 5 business days. Also, a sample of the mother’s blood is taken so that it can be compared to the miscarriage tissue sample. This way Natera is able to know for sure whether a normal female chromosome result is truly fetal or due to MCC.
What if I am miscarrying at home?
If you experience a miscarriage at home and can collect the tissue that was miscarried, your doctor may want to perform more tests, including chromosome testing, on this tissue sample.
When you have a miscarriage, the fetus, amniotic sac, and placenta, along with a large amount of blood, will be passed. If you miscarry sooner than the 8th week of pregnancy, the tissue that is passed looks no different from heavy menstrual bleeding. After the 8th week of pregnancy, more tissue will be passed which can look like large blood clots, or some pink/gray tissue, or even a sac. The tissue should be collected in a clean container such as a new Ziploc bag, plastic container (like Tupperware) or a specimen cup.
If you know you are going to have a miscarriage Natera can send you a specimen cup to place the tissue sample in. You may have already received this cup from your doctor’s office.
If you are unable to bring the miscarriage sample to your doctor’s office immediately, store the sample in the refrigerator (not freezer) to save the tissue.
It is important to know there is nothing you can do to prevent a miscarriage, and you did not cause the miscarriage to happen. Chromosome testing after a miscarriage may give you more information about the cause of your miscarriage. Please discuss this test with your doctor.
Will my insurance cover Natera's microarray testing with Parental Support?
If you wish, Natera will bill your insurance provider directly. All insurance companies are different, but most insurance providers cover part or all of the cost of testing. Contact Natera and your insurance provider to learn more about coverage.
About Chromosome Abnormalities
What are chromosomes?
Chromosomes are structures in each cell of the body that contain the genetic information, or genes, in the form of DNA. Healthy humans normally have 46 chromosomes arranged in pairs: 22 pairs of ‘autosomes’ and one pair of ‘sex chromosomes’ (XX in females or XY in males) for a total of 24 unique chromosomes (1 through 22, X, and Y)
What is a chromosome abnormality?
A chromosome abnormality is defined as too much or too little chromosomal material. A chromosome abnormality can be a whole extra or whole missing chromosome or can be an extra or missing piece of a chromosome.
What is aneuploidy?
An egg or sperm can form with an abnormal number of chromosomes, a condition called aneuploidy. Having an extra chromosome is called ‘trisomy’ and having a missing chromosome is called ‘monosomy.’
The majority of pregnancies with aneuploidy result in an early miscarriage. In fact, over half of all early miscarriages are due to aneuploidy. In some cases, a baby can be born with an abnormal number of chromosomes, which can cause birth defects and intellectual disability. A common type of aneuploidy is Down syndrome, caused by three copies of chromosome number 21 (Trisomy 21).
What is a translocation?
A translocation is a chromosome rearrangement in which a small piece of a chromosome breaks off and reattaches on another chromosome. People who carry balanced (reciprocal) translocations are usually healthy because no genetic material is missing, – but they have a higher chance for infertility, miscarriage, or having a baby with a chromosome abnormality.
What is an inversion?
An inversion is a chromosome rearrangement in which a piece of a chromosome breaks off, changes position, and reattaches to the same chromosome. People who carry balanced inversions are usually healthy because no genetic material is missing. They may have a higher chance for infertility, miscarriage, or having a baby with a chromosome abnormality.
What is the difference between a balanced and an unbalanced chromosome rearrangement?
A balanced chromosome rearrangement occurs when a piece of a chromosome breaks off and attaches to another chromosome or rearranges within the same chromosome, without any loss of genetic material. A person with a balanced chromosome rearrangement is called a “carrier” of the rearrangement. When a carrier makes sperm or egg cells, they may end up with extra or missing chromosome material. This can lead to a pregnancy with too much or too little genetic information, known as an unbalanced chromosome rearrangement. Pregnancies with unbalanced chromosome rearrangements can result in miscarriage, or in a baby with birth defects and/or intellectual disability.