turner syndrome

Hello, my first pregnancy I had a miscarriage at about 12-14 weeks.  An early ultrasound showed a cystic hygroma was the cause of the miscarriage.  A karyotype revealed my baby had turner's syndrome.  I am now pregnant again and about 13-14 weeks, 31 yrs old.  I had an NT test and results came back as normal but do not have the specific statistical number at this time, I'll see my doc this week for the number.  The ultrasound showed a normal nuchal fold and no hygroma.  My problem is I am extremely worried that I may have another baby with a geneitc defect.  I read that having a previous turner syndrome baby does not increase chances of another turner syndrome baby.  But my doctor said that my overall chances of having a baby with a genetic defect has increased.  Is this correct and do you know by how much? does my chances of having a baby with down syndrome also increase?  Also my doctor suggested to have an amnio is the only way to know for sure, but I am afraid of chance of miscarriage.  Genetically and statistically speaking I am torn on what to do, chance that everything is ok or chance an amnio.  Thank you.

[Lisa Kessler, MS, CGC]

I am sorry to hear about your miscarriage and wish you all the best with this pregnancy.  It is normal to feel worried about your current pregnancy.  I hope that the following information is helpful.  As you know, Turner syndrome is usually caused by complete or partial absence of one of the two X chromosomes normally found in women.  A pregnant woman’s age and her ethnic background are not thought to increase the chance that a pregnancy will have Turner syndrome.  In addition, Turner syndrome is not known to be associated with any environmental factors or genetic conditions. It appears to occur randomly in most cases.

You are unlikely to be at any higher risk for another pregnancy with a chromosome abnormality than other women your age in this pregnancy or any other pregnancy you have based on your history of one pregnancy with Turner syndrome. Your actual risk for your pregnancy to be affected with a chromosome abnormality is dependent on how old you will be when you deliver. For example, if you will still be 31, it is estimated at about 1 in 385, if you will be 32 it would be about 1 in 328.

About 3/100 babies is born with a birth defect.  Your overall chance of having a child with a birth defect is 3%, the same as the general population.  Amniocentesis is one diagnostic test that can confirm or rule out the presence of a chromosome abnormality.  Amniocentesis is generally performed from 15 to greater than 20 weeks, and risks for miscarriage range from about 1 in 200 to about 1 in 500.  It can be a very difficult decision about whether or not to pursue prenatal testing. Your NT test result sounds reassuring so far. When you receive your complete result with a risk number, this may help you decide whether you want to pursue an amniocentesis. It may help to meet with a genetic counselor to learn more about the risks and benefits of the procedure.  Meeting with a genetic counselor does not obligate you to have an amniocentesis.  You can find a genetic counselor near you on the National Society of Genetic Counselor’s website.

[sunkim]

Thank you very much for your response

[mcelwee23]

A related discussion, Turner Syndrome was started.