Posts Tagged ‘genetic counselor’

Today is World Down Syndrome Day

Wednesday, March 21st, 2018

What is Down syndrome?

Down syndrome is a chromosomal condition caused by extra genetic material. Typically, our cells contain 23 pairs of chromosomes. In the case of Down syndrome, a person has an extra full or partial copy of chromosome 21. This extra genetic material changes how the body and brain develop. People with Down syndrome have a few common physical traits, but each individual is unique and can lead a healthy active life.

We don’t know for sure why Down syndrome happens. Even though it’s a genetic condition, the majority of the cases are not passed on from the parents or family to the baby. Most cases happen because in the early stages of the baby’s development, there is a problem when the cells are dividing. However, there are some factors that may increase the risk of having a baby with Down syndrome, such as:

  • Mother’s age. The risk of Down syndrome increases with the mom’s age. Even though the risk is greater as your age increases, about 80 percent of babies with Down syndrome are born to women age 35 or less. This is because younger women have more babies than older women.
  • Having had a baby with Down syndrome. Up to age 40, for each pregnancy your chances of having another baby with Down syndrome is about 1 in 100 (1 percent). After age 40, the risk is based on your age. Talk to a genetic counselor to understand your risk of having another baby with Down syndrome.
  • Being a carrier of a genetic translocation. Both, men and women, can pass a genetic translocation to their baby. These cases are not very common. If you had a baby with Down syndrome before or if you or your partner have a family history of Down syndrome, it’s best to talk to a genetic counselor.

During pregnancy your health care provider will offer screening tests to see if your baby is more likely to have Down syndrome. These tests are offered to all pregnant women as part of regular prenatal care. However, a screening test won’t tell you for sure if your baby has Down syndrome. It only tells you if there is a higher risk. To know for sure you will need a diagnostic test.

How do you know if your baby has Down syndrome?

If you get an abnormal screening test result, your provider will recommend a diagnostic test. A diagnostic test will confirm if a baby has Down syndrome. There are few diagnostic tests:

  • Amniocentesis (also called amnio). This test checks the amniotic fluid surrounding your baby in the uterus to check for Down syndrome. You can get an amnio at 15 to 20 weeks of pregnancy.
  • Chorionic villus sampling (also called CVS). This test checks the tissue from the placenta to see if a baby has Down syndrome. You can get a CVS at 10 to 13 weeks of pregnancy.
  • Cordocentesis (also called percutaneous umbilical cord sampling or PUBS). For this test your provider inserts a thin needle into an umbilical cord vein to take a small sample of your baby’s blood to check for chromosome defects. You can get this test between 18 and 22 weeks of pregnancy. There’s a much greater risk of miscarriage with cordocentesis than with an amnio or a CVS. So you only get this test if other tests are unclear and your provider can’t confirm if your baby has Down syndrome any other way.

Down syndrome is also identified at birth by physical traits like: almond-shaped eyes that slant up, low muscle tone, a single line across the center of the palm of the hand, and a flattened face. But these traits won’t tell you for sure if your baby has Down syndrome, a chromosomal test call karyotype is needed to confirm this diagnosis.

If my first baby has a congenital heart defect, what are the chances my second baby will have one, too?

Friday, September 30th, 2016

pregnant mom with childThis is a question we received through AskUs@marchofdimes.org from a mom who is pregnant with her second baby. Congenital heart defects (CHDs) are the most common types of birth defects and if you already have a child with a CHD, you may wonder if your second child will have the same defect. The answer, though, is not a simple “yes” or “no.”

We don’t know the cause of most congenital heart defects. For some babies, their heart defects were caused by changes in their chromosomes or genes (which are passed from parents to children). Researchers have found about 40 gene changes (also called mutations) that cause heart defects. About 30 in 100 babies (30 percent) with a heart defect also have a chromosomal condition or a genetic condition. So if you, your partner or one of your other children has a congenital heart defect, your baby may be more likely to have one, too.

But CHDs are also thought to be caused by a combination of genes and other factors, such as things in your environment, your diet, any medications you may be taking, and health conditions you may have. Conditions like diabetes, lupus, rubella and even obesity can play a role in causing CHDs.

So what is your risk?

The chance of having another child with a CHD depends on many factors. It is best to meet with your health care provider and a genetic counselor who can better assess your risk. A genetic counselor is a person who is trained to help you understand how genes, birth defects and other medical conditions run in families, and how they can affect your health and your baby’s health.

 

Trisomy Awareness Month

Friday, March 4th, 2016

chromosomes1Have you ever heard of “trisomy”? Trisomy is a chromosomal condition that is the result of a mistake in cell division. Chromosomes are the structures in cells that contain genes. Each person normally has 23 pairs of chromosomes, or 46 in all. An individual inherits one chromosome from the mother’s egg and one from the father’s sperm. When an egg and sperm join together, they normally form a fertilized egg with 46 chromosomes.

Sometimes something goes wrong before fertilization. A developing egg or sperm cell may divide incorrectly, causing that egg or sperm to have an extra chromosome. When this cell joins with a normal egg or sperm cell, the resulting embryo has 47 chromosomes instead of 46.

Babies with trisomy are born with an extra copy of a specific chromosome in most or all of their cells. This means that they have three copies of this chromosome in each cell rather than the typical number, which is two.

Although trisomy can occur with any chromosome, there are a few conditions that are most often associated with an extra chromosome. They are:

  • Trisomy 21 or Down syndrome: Down syndrome is one of the most common birth defects. In the US, about 6,000 babies (or 1 in 700) are born with Down syndrome each year. Most affected individuals have intellectual disabilities within the mild to moderate range. Although health conditions such as heart defects and vision and hearing problems are associated, most of these can be treated, and life expectancy is now about 60 years
  • Trisomy 18 is also called Edward syndrome. Trisomy 18 occurs in about 1 in 5,000 live births each year. Affected individuals may have heart defects, significant intellectual and developmental delay, and other life-threatening medical problems.
  • Trisomy 13, also known as Patau syndrome, occurs in about 1 in 10,000 to 16,000 live births each year worldwide. Individuals with trisomy 13 often have heart defects, brain or spinal cord abnormalities, severe intellectual and developmental disabilities, and multiple physical problems in many parts of the body.

It is important to understand that every individual with a trisomy is unique and not all of them will have the same symptoms. The problems depend on which chromosome is duplicated and how much of the extra chromosome is present. Health conditions that may be associated with trisomy include heart defects, vision or hearing problems, and intellectual and developmental disabilities.

If your baby or someone in your family has a trisomy, you may want to talk to a genetic counselor. A genetic counselor is a person who is trained to know about genetics, birth defects and other medical problems that run in families. She can help you understand the causes of chromosomal conditions, what kind of testing is available, and your chances of having a baby with these conditions. If you already have a baby with a trisomy, the chances of having another baby with the same condition are usually low.

Have questions? Email us at AskUs@marchofdimes.org.

Holidays are a time for family

Monday, November 24th, 2014

Family at Thanksgiving dinnerAnd learning about family health history! I recently visited some relatives that I had not seen in years. After we caught up, they mentioned to me that colon cancer runs in that side of the family. This was news to me, as I did not know much about our family’s health history. At my next doctor’s appointment I told my doctor what I had learned from my relatives, and we made a plan on how to manage my health care going forward.

At Thanksgiving, you may be getting together with your family over a delicious turkey dinner. This is a great time to bring up your family’s health history. You may discover important information to keep in mind at your next doctor’s visit like I did.

On our website, we have a lot of helpful tips on how to talk to family and relatives, how to use the information they share, and what to do if some family members don’t want to talk about their health.  You can also use our Family Health History form to help you start a conversation with your family.

Knowing your family’s health history is helpful, especially if you are pregnant or thinking about becoming pregnant. If you learn that your family has a health condition that gets passed from parent to child, you may want to see a genetic counselor. This is a person who is trained to help you understand how conditions run in families and how they can affect your health and your baby’s health.

Enjoy spending time with your family this Thanksgiving, and learn about each other’s health at the same time. You may discover a few new things that can help you make healthy decisions for your future.