Signs and Symptoms
Down syndrome is a genetic condition caused by extra genes from the 21st chromosome that result in certain characteristics including some degree of mental retardation, or cognitive disability, and other developmental delays. The incidence of Down syndrome in the United States is about 1 in 1,000 births. There is no association between Down syndrome and culture, ethnic group, socioeconomic status or geographic region.
Age-related Risks
Generally, the chance of having a Down syndrome birth is related to the mother’s age. The odds of having a child with Down syndrome at age 35 are about 1 in 350. Under age 25, the odds are about 1 in 1,400. At age 40, the odds are about 1 in 100.
Types of Down Syndrome
There are three types of Down syndrome:
Trisomy 21 — An estimated 95 percent of people with Down syndrome have Trisomy 21, meaning an individual has three instead of two number 21 chromosomes. We normally have 23 pairs of chromosomes, each made up of genes. During the formation of the egg or the sperm a woman’s or a man’s pair of chromosomes normally split so that only one chromosome is in each egg or sperm. In Trisomy 21, the 21st chromosome pair does not split and a double-dose goes to the egg or sperm. An estimated 95 percent to 97 percent of the extra chromosome is of maternal origin.
Translocation — This occurs in about 3 percent to 4 percent of people with Down syndrome. In this type, an extra part of the 21st chromosome gets stuck onto another chromosome. In about half of these situations, one parent carries the extra 21st chromosome material in a “balanced” or hidden form.
Mosaicism — In mosaicism, the person with Down syndrome has an extra 21st chromosome in only some of the cells but not all of them. The other cells have the usual pair of 21st chromosomes. About 1 percent to 2 percent of people with Down syndrome have this type.
In addition to mental retardation and other developmental delays, some common physical traits are an upward slant of the eyes; flattened bridge of the nose; single, deep crease on the palm of the hand; and decreased muscle tone. A child with Down syndrome, however, may not have all these symptoms.
Typically, parents of Down syndrome babies don’t have any symptoms themselves even though they may carry an abnormal gene.
Risk of Recurrence
After the birth of a child with Down syndrome, the risk of having a second child with Down syndrome depends on what caused the condition in the first child. A medical geneticist or genetic counselor should be consulted to get more precise information on the risks. The following are some general guidelines:
Trisomy 21 — The risk of Down syndrome recurring is either 1 percent to 2 percent or the risk based on the mother’s age, whichever is higher.
Translocation — The risk of Down syndrome recurring depends on if the translocation was inherited or not inherited. If not inherited, the risk is the same as the risk based on the mother’s age. If inherited, the risk depends on the type of translocation and the sex of the parent carrying the chromosome abnormality. For the more common “balanced” or hidden translocation, the risk ranges from about 3 percent when the father is the carrier to about 12 percent when the mother is the carrier. If a parent carries a rare “21;21″ translocation, the risk for Down syndrome is 100 percent.
Mosicism — The risk is about the same as risk based on the mother’s age.
Reviewed by health care specialists at UCSF Children’s Hospital.
Last updated March 21, 2008
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I hate the transition to a toddler bed, my hubby changed my oldest’s baby into the toddler bed way too soon! No more cage, so you wind up having to grow WITH the child and re-adapt to THEIR newly found and exhausting freedom,right?! Well, congrats on her graduation. I’m looking forward to getting to know you and your family as well. Thanks for the nice message. 
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i am about 3 months into my pregnancy, my boyfriend has a sister with down syndrome and i do not have any family health concerns. i just wanted to know whats the percentage of the baby having it and if i should be more concerned then ever? i am going to get the test done for it but i just feel really concerned at this point.
hi i just found out through my blood test that i am of high risk to be having a baby with ds a friend mentioned typically you are larger in this pregnancy than others (which i am) did any of you find this to be true?
many thanks
rebecca
Here is a great site to learn about downs syndrome and other birth defects.
Good luck!
Thanks for sharing.
Do you have any others? Also, wondering if you might be interested in sharing resources with the community…Many ppl here are starving for information and I simply don’t have enough time…
Any thoughts?
We gave birth to a child with down syndrome just 4 months ago. She was diagnosed at birth, and we were shocked. Despite this, I can assure anyone who is reading this that it will change your life in a positive way. Our daughter is beautiful. LIFE is beautiful. Do not despair. Fight for your sons and daughters. It is worth the journey. It is worth the struggle. There is hope and resources for you. When our daughter smiles…and your son or daugher WILL SMILE!….it will melt you and nothing else matters.
What a wonderful comment. Thanks so much!
Justin
It is wonderful to hear parents who have children with Down’s syndrome talk with so much love. I denied an amnio despite doctor’s suggestions because I had an ivf pregnancy and I could not afford to risk it. My risk during the first timester screening came at 1:162 and since then I have to admit that my life has changed. At moments I am feeling super strong saying to myself that I can do it, it will not affect my family, we can handle it because we have a lot of love to give and everything will be ok, at other moments i am feeling lost afraid about my baby’s future, about how society will treat my son, will it affect my elder daughter’s life,will it affect my relationship with my husband? I am due in January so I have another month and a half to torment my soul with all the what ifs. I used to think that i was a good person and now I question myself how good can I be if I am so afraid of having a child with Down’s, will I be a good mother to him?
Eleutheria,
Enjoy your pregnancy!!!! If you have a child with down syndrome, I promise you all will be ok. It is a time of adjustment but all of your fears will melt when you look into your child’s beautiful little eyes. 1:162 are very small odds so please don’t worry. You’ll cross that bridge if it gets there.
Just that you are thinking about being a good mother means that you will be! Again, enjoy your pregnancy. All is going to be great.
Justin
I turned 41 last month and found out I am pregnant a few days before my birthday. I have a sister who has DS, my mother gave birth to her when she was a few years older than I am now. I am concerned about the prospect of having a Down’s child even though I know how loving and sweet they are. I don’t know how to come to peace with the idea that it might happen.
Patty,
Don’t worry until there is something to worry about. Having a child with DS is a challenge but also a wonderful gift. If you should happen to be given the wonderful responsibility of being a parent of a child with Down Syndrome, you will love that baby and cherish the experience in a way that you can’t understand right now.
Have a wonderful pregnancy and please don’t worry … everything will be wonderful for you and your family.
Justin
Enjoy the journey of being pregnant!! There is no other journey like it. I became pregnant at 38 and was not large in size at all. I too denied and amnio as I did not want to risk the complications, and we decided to have the baby no matter what. God blesses people he knows can handle the joys and trials of having a child with Downs. Any negative thoughts you may have (and you’ll have more) are normal. No matter the parent, no matter the child, you will always wonder if you are doing a good enough job. We are all doing the best that we can with the resources we have….And use those resources available to you – that’s what they are there for.
That baby will bring you joys you didn’t know were possible. Enjoy the journey!
This past month I have lost my baby at only 15 weeks of pregnancy. I did have an Amnio done, it was determined that I had a baby girl and that she indeed had downs. It was detected at 12 weeks of pregnancy that there was a high risk of DS, but the major concern was fluid around her heart. I was told that her heart defect was a result of the Downs. I am wanting to try again, for another child. My concern is that I will have to loose another baby … what are my chances of having another baby with DS or more importantly, my chances of loosing my baby?
Also, is there support groups and/or other sires that I can get this imformation from?
We have a daughter with Downs who just turned two. In late June 2009, we found out we were pregnant again, and very much looking forward to the journey – what ever the outcome. Well, it wasn’t meant to be, and in August I had a miscarriage. The lemonade out of the lemon, was that the child was chromosomally correct (no DS). While your odds of conceiving another child with DS are greater (especially if your age is a factor), there is still the hope that you will have a perfectly fine child as well. Again, enjoy the ride!
My little brother was born with down syndrome 4 and a half years ago. He is probably one of the most intelligent 4 year olds i have ever met. He is extremely smart an very talented ad loves to color. It is a challange when they are growing up, but they are so cute and loveable that it gets easier. So dont be scared, there really isnt anything to worry about.
hello im monique richmond im pregnant with my third child i was tested for down syndrome but they didnt yet do the fluid test the one they do from the tummy the doctor said that i may be ok the blood test tested 1 out of 650 for down syndrome so will i be ok no one in my family has it i have a 20 yr old son a 18 yr old daughter a 8 yr old daughter they all were healthy i am 40 yrs old i had my oldest at 20 my oldest daughter at the age 23 the youngest daughter at 33 i am now 40 i was a little worried but i am ok i believe in god i just needed some answers.god bless all the familys who are deali with down syndrome may god give them the blessing.please give me the answers .
Monique,
I hope things worked out for you.
Justin
I’m seventeen, and I am five months pregnant just about with a baby girl.We got a call three days ago from my OB, and he said the blood test came back positive for down syndrome. Whether my baby has down syndrome or not, i’ll love her with everything i have in me. I’m so scared, that I wont be able to give her what she needs. Any advice?
Hi Shawnda…My advice to everyone is always just to love your baby little girl with all your heart and the rest will work itself out and be wonderful in a way that you can’t understand right now…We have all had the exact same feelings as you and one thing that I’ve found to be universal among us is that we inevitably all feel that our lives change and our experiences become more meaningful and our perception of the World a little clearer.
Feel free to email me if you have any questions or just want to talk. We wish you the best with your baby girl. Life is so interesting .. sometimes we can’t explain why things happen but more often than not, they seem to happen to people that can handle them.
Take care,
Justin
Hey Justin! I think this website is wonderful. You have done a great job. I did post on the expecting page but I wanted to do it here also. At 17 weeks my ob noticed that our daughter may have a heart defect, at that time the quad blood test they do did come back negative at 20 weeks we found out that yes in fact she does have a av canal heart defect, at 21 weeks we did the amino and at 22 weeks we did find out that all 4 groups of cells they tested did grow a 3rd 21st. I do have to say I was divested, I know you know all the emotions of what you go though. I blamed myself and wanted to know what I could have done to cause this, I had done everything 100% by the book. I learned there wasn’t anything I did to cause this, it is just something that happens. I was sitting in the doctors off crying and the genetic consular came in and handed my husband and I two books, on the cover of both of those books was the most beautiful babies with down syndrome. I remember crying and looking at my husband and saying they are beautiful. We are not at week 26!! We are taking everything one day at a time and learning as much as we can about down syndrome and av canal as we can before she gets here. We have also looked into places to have her heart surgery. do you have any suggestion of the best way to be prepared??
Thank you! My only suggestion to you is be prepared to have a wonderful little baby that will keep you awake…Get some sleep as often as you can
Your baby is going to be great! You are going to develop a bond with her that I can’t even explain right now. Something will change in you and your husband that will be magical. Just as any new parent, your view of the World will become clearer in a way that you can’t never understand right now.
It is impossible for me to relate what it will be like for you but I promise life will be better for you once your little baby comes. I tend to stay away from the various platitudes that are often used but the one that I always think is a truism is that you have been given an opportunity and a gift and once you have a chance to experience that gift, the pain will be a distant memory.
Please keep in touch. I look forward to getting to know you and your family more.
Sincerely,
Justin
My husband and I have 3 beautiful daughters! The youngest- 14months old, has DS. She is the sweetest baby! We found out at 5months pregnant that she had 2 holes in her heart and most likely had DS, we did the blood test and it was NEGATIVE, and I refused an amnio (fear of big needles). It was a very long and emotionally draining pregnancy. When she was born we knew right away that she was DS positive. At 4 months old baby girl had surgery to fix her heart- absolutely heart wrenching for me to see her going thru that. Today she is so beautiful, learning to crawl, rolls everywhere, has a few words, and loves to play with her sisters, but most of all her big sisters love their baby. To look at her most people don’t notice the Downs. To those of you who are just finding out, I say stick with it, because it gets easier.
I could not agree more..Thank you for helping and sharing!
Justin
Hi,
I’m Nikki and I have a 6 month old son with ds. I have an older son who is 31/2 years old. I had testing done for both of my children to find out if they had ds. In the case of my second son the doctor didn’t bother to read the results and told me everything was fine. My son was born with ds and 2 holes in his heart which were closed at 3 months of age.
I find that I’m still having a really, really, hard time accepting his ds. I have tried many things to help: support groups, counseling, even antidepressants for a short time. I just feel like his special needs are going to be a life long burden. I don’t know how to feel better about this. His smile is sweet, like all babies, but it doesn’t make me see past the ds. Am I alone feeling this way?
Nikki
Hi Nikki,
i’m sorry you are having a difficult time…We never forget that our children have down syndrome either. It is hard on all of us. we all love our children but at the same time there are times when the unknown is debilitating and scary. I will say though that our children belong in this World and have a right to life just as much as any other person. Historically, different ethnicities, sexual orientations, and even sexes were considered to be lesser than other groups. The world became more enlightened and accommodating and I believe the same thing will be the case for our children. You have had a relationship with your child for almost 6 months and I’m sure you are entering a phase where the gap in other children’s abilities and your son is starting to widen. this can be difficult.
its good that you have been seeking help and engaging with others…finding the right support is very much the key to becoming more comfortable. my wife and I had to try a few times to engage with the right set of people to help us through things.
also realize, that things have progressed so significantly from the bad old days…early intervention, therapy, inclusion, etc have been proven to yield amazing results — many of our children will grow up and go to college, learn to drive, have a family, and live independently. the responsibility will be on you to help your child down this path but just as any typical child, you will shape your child’s future immensely if you put in the work. make sure you get support from the state…this is the time to get this going. My son started at around 6 months.
this is the time when we as parents need to take a deep breath and buck up and realize that we are the center of our child’s life and they depend on us for everything. you are not alone at all in this … please come back here and visit and talk anytime you need.
the only thing that matters is you and your family –everything else is just context.
Justin
Thanks Justin,
I feel like I finally turned a corner. I am beginning to see my son as a person as opposed to a diagnosis. It was hard to do that initally with all the doctors appointments. However, now that he's becoming his own person with his own cute personality, it's a lot easier. I know I'll still have low times, but I think I was making things way too hard on myself by worrying to much about the future. The future will be whatever it is. It won't stop me from trying to do the best for my son to reach his potential. I just don't need to stress out as much as I did about it. Thanks again for your help.
Nikki
You epitomize everything that is good in our World. It is so easy to be selfish and negative. The fact that you have taken on this responsibility and march forward is the best / most important thing to do. Just love that kiddo and everything is going to be wonderful.
As I said before — this is between you and your baby. Nothing else really matters. I look forward to getting to know you and your family better.
Justin
HI Nikki. I have a 4 year old son with ds. It took me 3 years to get over the feeling of loss and deep, deep sadness. I had another child 15 months after Zach and I know that this helped but what really made a difference was getting therapy within a few months of having Zach. I underwent a type of therapy called choice therapy which helped me to deal directly and immediately with any negative thoughts and fears that I had around the future. It involves admitting what you are feeling, accepting that the fear is real but that there is a very realistic chance that the 'fear' may be unfounded and if the worst happens that you know in your heart you can deal with it. I admitted from the beginning to everyone how devasted I felt. In other words, I really tried to accept the grief I was feeling and to live through it BUT at the same time, I tried to just love this new baby who was beautiful and so easy to love. What I can say is everything you are feeling is alright and that 4 years on I still feel sad, but only occasionally. The pain will go and you will wonder why you felt such sadness.
Hi everyone. My 4 year old was trained last September but since Christmas 2010 started to have accidents again. He is suffering from constipation but we have forged on. He won't tell us when he wants to go anymore but when we take him, every hour or so, he usually goes. He is seeing a paediatrician about the constipation and we are using laxatives but he seems to have no motivation despite us using props and bribes. Can anyone out there advise us?
hi my name is ariel, i do not have a baby with down syndrome but i do have a sister with it. when i first found out that she had down syndrome i was a little hurt. we found out a few months after she was born. my little sister is now nine months going on ten months. she is the joy of our life and the most precious thing i have ever saw. she is going to her therapy and is developing great. the doctor says that her case of down syndrome is very mild so it shouldnt affect her that much. i would just like to encourage any one who has a baby or sibling with down syndrome to just show the child as much love as you possibly can because that is what make things a whole lot better for the child and for you. GOD bless!
Thank you for your comment. We very much appreciate your positive sentiments and wish you and your family the best.