# Risk of down syndrome?



## vikster

Hi girls, one of my mums relatives (either cousin or second cousin, I never met that side of the family so not sure) had downs syndrome and I was wondering if you knew what the chances would be of my child having it? My mum had the amnio test when she was pregnant with me and by brother and we were not affected. I have heard that there are other tests that they do now or things that they look for at scans, what are they? Is a baby having downs genetic or is it just random? 

Thanks xx


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## Unbridled

97% percent of the time Down Syndrome is caused by a random genetic anomaly in either the sperm, or, more likely, the egg, which causes an extra copy of the 21st chromosome to be copied into an embryo's DNA. This happens at conception and it is not hereditary. There _is_ a type of Down Syndrome, called translocation, that can be passed from either the mother or father, but it is extremely rare and can be detected via genetic testing of the parents before pregnancy occurs. Children who are born with any type of DS are usually tested within a few days of diagnosis to see which type they have. If a child has translocation Down Syndrome, it is recommended their siblings be tested as well. This is because a sibling can have what it known as a "balanced translocation", which means they carry an extra copy of the chromosome in some, but not all, of their DNA. They themselves will not experience any symptoms associated with DS, but they can pass it on to their children.

Despite popular belief, Down syndrome isn't something that only, or even mostly, occurs in older mothers. While your risk of giving birth to a baby with DS increases as you age, the majority of babies with DS are actually born to women under the age of 35. This is because more women of that age give birth. My mother-in-law, for instance, gave birth to a child with Down syndrome when she was only 19. He was her first natural child out of three and he's the only one affected. No one else on either side of hubby's family has DS.

I understand your being concerned about this since you have a relative with DS. It's been a worry to me my entire pregnancy despite the fact that I know hubby's brother has the more common non-hereditary type.

Several screening tests are offered in the first and second trimesters, which will help determine your risk of having a child with DS. These include the NT scan and quad screen. The NT scan is an ultrasound that checks for "soft markers" of the disorder. These markers include an enlarged nuchal translucency (fluid at the back of the neck), lack of a nasal bone, and bright spots on the heart and other organs. The presence of soft markers does NOT indicate the presence of DS; it only shows a risk. The quad screen blood test is similar in that it will test for certain hormone levels associated with DS, but it will not tell you whether your child has it. If your screening tests come back high risk, you will then be offered diagnostic testing.

Diagnostic testing can be either a CVS or amniocentesis. The CVS is an early test during which a small piece of the placenta is removed and tested; the amnio, which can be performed later, is a test in which amniotic fluid is removed and tested. Both tests carry a very small risk of miscarriage and can take a few weeks to complete. Unless you're considered high risk before your pregnancy, most doctors recommend you have the screening tests before considering the more invasive diagnostic testing. However, if this is something that you feel will weigh heavily on your mind, you can request a diagnostic test. I would have done that myself had my insurance company been willing to pay for it. Unfortunately, they weren't.

There is also a new blood test to check for DS which is supposed to be more accurate and non-invasive. However, as far as I know, it's not being offered in the States yet and I don't know much about it. Maybe someone else can tell you more about that.

I hope the information I've given you has been helpful. :hugs:


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## vikster

Unbridled, thank you, that is very helpful indeed. My mum is an only child so although the cousin is a relative, I dont think of them as family and Infact I don't even know if they are a he or a she! My grandparents were both from large families and were both one of about eight kids so I will ask my mum a bit more. It has never occurred to me before and from what you posted, I don't think my risk will be any higher than anyone else and if they test as standard for signs of risk then I would know from that xx


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## vikster

Oh, forgot to say, congrats on your pregnancy and good luck xx


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## NaturalMomma

Trismony 21 (DS) occurs around 9 times for every 10,000 births. I would say it is unlikely that your child will have Trismony 21. Amnio is still common for detecting Trismony 21, as well as some other tests. I wouldn't do amnio unless the Doctor suspected it.


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## MollyWeasley

I plan on skipping any extra tests for DS when the time comes, because knowing either way wouldn't change anything for me and DH. We wouldn't terminate a pregnancy for DS, and there's nothing extra they do during pregnancy to help with development if they suspect downs (as far as I know).


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## I Love Lucy

mollyweasley said:


> i plan on skipping any extra tests for ds when the time comes, because knowing either way wouldn't change anything for me and dh. We wouldn't terminate a pregnancy for ds, and there's nothing extra they do during pregnancy to help with development if they suspect downs (as far as i know).

wss ^


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## lilyanne

I Love Lucy said:


> mollyweasley said:
> 
> 
> i plan on skipping any extra tests for ds when the time comes, because knowing either way wouldn't change anything for me and dh. We wouldn't terminate a pregnancy for ds, and there's nothing extra they do during pregnancy to help with development if they suspect downs (as far as i know).
> 
> wss ^Click to expand...

Same here


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