Down Syndrome Risk in Pregnancy: Factors & Considerations

Question
Dear Dr. Rappaport,

I am a 38 year old woman who will turn 39 in a month. I consider myself very healthy for my age, as I am an appropriate weight (I am 5'3" and weight about 112) and I exercise regularly. I have one healthy son who is nine now.  My husband and I had fertility problems and finally conceived when I was 29 as a result of drugs and insemmination.  We had tried for several years, but after a surgery to open up one of my tubes, we did shots and insemmination and became pregnant. My pregnancy was uneventful and I had no problems with labor and delivery.   We have always wanted to have a second child.  Two years ago, we attempted the same prodedure and were successful, only to have a miscarriage when I was three months along.  Then  four months after that, I became pregnant naturally and it was very unexpected.   We were excited but that pregnancy ended because it was ectopic (sp?).  My OBGYN said that I would now have a 25% chance of having another tubal pregnancy and that if I did get pregnant again, I would have to be monitored very closely at first. My husband and I gave up the idea for awhile, but are now seriously considering trying to get pregnant. I am very scared of having another tubal.  I am also very scared of having a baby with Down's Syndrome.  I know that since I am almost 39, I have an increased risk of this happening.  What are your thoughts on this?  What are my risks and should we just be happy that we have one healthy child? Part of me feels that we should be happy and feel blessed we have him--and we do!  He's a great kid!  However, the other part of me feels that we are depriving him of a brother or sister and that we owe it to him to at least try one more time. He knows about our previous failures and has expressed the desire to have a sibling. I do worry about him having to deal with future faiure. Any help and advice would be greatly appreciated!  
Beth


Answer
If you have not conceived yet, then you probably would be 40 by the time of delivery if you became pregnant now. At the age of 40 the risk of Down's syndrome is 1:100. This is a very high risk for Down's. However, you can always have an amniocentesis at 18 weeks gestation which can absolutely diagnose any chromosomal abnormality and, if you do have any abnormal chromosomal defects, you can terminate the pregnancy before 22 weeks gestation. If you do give birth to a baby with Down's syndrome, you have to realize that the baby will be dependent on you for his or her entire life and, at your age, that may be difficult for you. A sibling of a Down's syndrome child has some difficulties with the absurd stigma surrounding the syndrome and may have social difficulties surrounding his brother or sister. This comes into play when he meets prospective in-laws, shool friends, etc. On the other hand, babies with Down's syndrome are very loving children and there have been vast improvement in training and education in recent years.
Whatever you choose, there are always choices. Good Luck to you.