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Prenatal Screening Program

ā€‹Two Children Sitting at a Table Coloringā€‹

Getting an unexpected prenatal screening result

When your prenatal screening result shows an increased chance of a genetic condition or birth defect in your fetus

Your doctor will tell you if your prenatal screening result shows your fetus has an increased chance of a genetic condition or birth defect screened for by the Prenatal Screening (PNS) Program. Please discuss it with your primary care provider. You can refer to one of the following booklets to find out about specific screening results.

This web page will help you understand the PNS Program and your options:

  1. Provides information on what to expect from the prenatal screening process
  2. Explains the services available to you
  3. Discusses your options for genetic counseling, testing, and the pregnancy
  4. Includes what it is like to raise a child with a genetic condition or birth defect

Prenatal screening results

Your prenatal care provider shares prenatal screening results with you. Getting unexpected prenatal screening results can create uncertainty.

The prenatal screening result could show an increased chance that your fetus has a certain genetic condition or birth defect. The PNS Program screens for Down syndrome (trisomy 21), trisomy 18, trisomy 13, and neural tube defects, like spina bifida and anencephaly.

This screening result does not always mean that the fetus has a genetic condition or birth defect. Prenatal screening only estimates the chances of certain genetic conditions and birth defects. Diagnostic testing is needed find out if a condition or defect does exist.

If you got prenatal screening through the PNS Program, and screening results show an increased chance of a genetic condition or birth defect, your prenatal care provider will offer follow-up services at a state-approved Prenatal Diagnosis Center.

Program-provided follow-up services include genetic counseling, ultrasound exams, and diagnostic testing to find out if a condition or defect exists. These services are available to you at no additional costs. They are included in the initial program fee. You decide if you want any of the follow-up services.

Follow-up services

Genetic counseling

Genetic counseling is the first service offered at a state-approved Prenatal Diagnosis Center.

A genetic counselor discusses your screening result and what it means. They will also review your familyā€™s health history. If you choose to have diagnostic testing, genetic counselors can also help you understand your test results.

Genetic counselors provide a level of detail that doctors often donā€™t have time to address during a routine prenatal visit. The genetic counselor will give you information about your situation, the genetic condition or birth defect, and your options. They include the following:

  • No further testing
  • A detailed ultrasound (sonogram)
  • A diagnostic test: chorionic villus sampling (CVS) or amniocentesis

With a genetic counselorā€™s help, you can better understand the available diagnostic tests, the genetic condition or birth defect, and what might be best for you. Be sure to ask the genetic counselor any questions you may have. You decide if you want any additional follow-up services after genetic counseling. The other options are described in more detail below.

Ultrasound (sonogram)

Doctors with special training can do an ultrasound. It gives a very detailed picture of the fetus and checks its age. It may identify some birth defects. However, it is not a way to find out for certain if your fetus does have a genetic condition.

You can have this ultrasound even if you decide not to have chorionic villus sampling or amniocentesis.

Diagnostic tests

Chorionic villus sampling

Chorionic villus sampling (CVS) is a test that can tell if the fetus has a genetic condition. CVS can be done from 10 through the end of 14 weeks of pregnancy.

For this test, an experienced doctor removes a small amount of tissue using a very thin needle or tube. The fetus is not touched. The tissue contains the same chromosomes as the fetus.

The test looks at the chromosomes. Chromosomes help the fetus develop and are found in every cell in the body. The chromosomes are counted and examined.

CVS is a test done by a medical expert at a state-approved Prenatal Diagnosis Center. The risk of miscarriage from CVS is less than 1 in 450. The CVS result is usually ready in two weeks.

Amniocentesis

Amniocentesis is a test that can tell if the fetus has a genetic condition. This test can be done starting from 15 weeks of pregnancy.

For this test, an experienced doctor takes a small amount of the fluid around the fetus with a thin needle. The fetus is not touched. This fluid contains cells from the fetus. The chromosomes in these cells are counted and examined.

Amniocentesis is a test done by a medical expert at a state-approved Prenatal Diagnosis Center. The risk of miscarriage from amniocentesis is less than 1 in 900. The amniocentesis result is usually ready in two weeks.

The genetic counselor can help you understand your diagnostic test results and the genetic condition or birth defect. The genetic counselor can also help you understand your options following diagnostic testing. It is your choice what to do.

Why you might consider diagnostic testing

Screening results just give an estimate of the chance for a condition or defect. Some fetuses who have a screening result suggesting an increased chance of a birth defect do not actually have one. Getting diagnostic testing can tell you for sure whether your fetus has a genetic condition or birth defect.  

Whether you choose diagnostic testing is a personal decision. Before deciding on testing, some people ask themselves the following questions:

  • ā€œHow much do I want to know?ā€ and
  • ā€œWhat would I do if my fetus has a confirmed diagnosis?ā€

You can discuss your choice with a genetic counselor.

Whether to test is entirely up to you. Diagnostic testing information may be used for the following:

  • Assurance about whether or not the fetus has a diagnosis
  • Planning for a potentially complicated delivery
  • Planning for a future with a special needs child
  • Planning an adoption
  • Planning an abortion

If you have diagnostic testing and the results confirm a genetic condition or birth defect, genetic counselors are available to help you review your pregnancy options.

Getting unexpected screening results

The PNS Program screens for Down syndrome, trisomy 18, trisomy 13, Turner syndrome, Klinefelter syndrome, Trisomy X, XYY, and neural tube defects, like spina bifida and anencephaly. Each of the conditions is very different and can affect people differently.

When prenatal screening shows a fetus might have a genetic condition or birth defect, people often have many questions based on the unexpected screening results. People may consider the following questions:

  • ā€œWhat is the quality of life for people with this condition?ā€
  • ā€œWhat medical concerns might be involved.ā€
  • ā€œHow is it different to parent a child with a condition compared to parenting in general?ā€
  • ā€œWhat social support might be needed from family and friends?ā€
  • ā€œWhat costs might be involved with raising a child with a physical or cognitive condition?ā€
  • ā€œWhat services and supports are available?ā€

Most expecting parents who get an unexpected prenatal screening result say they want more information right away about the condition such as:

  • Impact on life expectancy
  • Possible medical concerns
  • Supports and services

Taking the time to evaluate your options will help you make the best decision for you, your pregnancy, and your family.

Supports and services are also always improving outcomes for people with certain genetic conditions and birth defects. Medical advances, for example, can improve treatment or care. It is important to get the latest information about a condition. Information about a certain condition can give a general idea about the range of life outcomes. However, each person is unique.

Some expecting parents may want to connect with local or national support groups. Specialty clinics can also provide you more information, support, and care. Specialty clinics can be found in California for many conditions.

Below are overviews of each condition and resources to support you in learning more, as well as available supports and services. Included are the contact information for national support organizations. Many of them have local chapters as well.

General resources about different conditions for parents

Supports and services available in California for people with disabilities

Finding out about certain genetic conditions

Down syndrome or trisomy 21

Down syndrome usually occurs when a person has an extra copy of chromosome 21. Chromosomes are one of the genetic building blocks for all people. There are about 250,000 people nationwide living with Down syndrome. It is found among all cultures and economic classes.

The range of medical conditions and abilities can vary widely for people with Down syndrome. Each person with this condition has their own strengths and weaknesses that no one can predict before birth. In general, most people with Down syndrome have mild to moderate intellectual disabilities. Most can communicate verbally and take care of their basic needs (such as bathing, toileting, dressing, etc.).

Down syndrome can also cause low muscle tone and higher chances for some health problems such as heart conditions. However, most health concerns can be successfully treated or managed. The average life expectancy for a person with Down syndrome is about 60 years.

Like all people, people with Down syndrome face challenges. Recent advances in healthcare, education, and public attitudes have greatly improved their lives. This progress has given them more opportunities as valued members of their families and communities. This means that more people with Down syndrome are finishing school, finding jobs, and forming meaningful relationships.

[Used with permission from Lettercase ā€œUnderstanding a Down Syndrome Diagnosis Overview.ā€]

Recommended resources

 Parent support groups

Trisomy 18 (Edwards syndrome)

Trisomy 18 is caused by an extra copy of chromosome 18. Trisomy 18 usually causes significant health issues and intellectual disabilities. Almost 3 out of 4 (about 72%) of trisomy 18 pregnancies result in miscarriage or stillbirth between 12 weeks to term.

Currently, fewer than 1 in 10 (10%) of babies born with trisomy 18 survive beyond their first birthday. Some children and adults can live longer with intensive medical care.

Those who survive with trisomy 18 have profound disabilities. They will not gain the characteristic developmental or age-specific skills compared to others of the same age group, but they can make some progress. They can build meaningful relationships with friends and family.

Families affected by trisomy 18 often say that they want the opportunity to determine how little or how much medical care their fetus or child receives. They also want access to support services and grief counseling as needed.

[Adapted with permission from Lettercase ā€œUnderstanding a Prenatal Screening and Testing for Chromosome Conditions.ā€]

Recommended resources

Parent support groups

Trisomy 13 (Patau syndrome)

Trisomy 13 is caused by an extra copy of chromosome 13. Trisomy 13 usually causes significant health concerns and intellectual disability. About half of trisomy 13 pregnancies result in miscarriage or stillbirth between 12 weeks to term.

Currently, fewer than 1 in 10 (10%) of babies born with trisomy 13 survive beyond their first birthday. Some children and adults can live longer with intensive medical care.

Those who survive with trisomy 13 have profound disabilities. They will not gain the characteristic developmental or age-specific skills compared to others of the same age group, but they can make some progress. They may build meaningful relationships with friends and family.

Families affected by trisomy 13 often say that they want the opportunity to determine how little or how much medical care their fetus or child receives. They also want access to support services and grief counseling as needed.

[Adapted with permission from Lettercase ā€œUnderstanding a Prenatal Screening and Testing for Chromosome Conditionsā€]

Recommended resources

Parent support groups


Starting April 1, 2024, the CA PNS Program will add sex chromosome aneuploidies (SCAs) ā€“ also referred to as X and Y chromosome variations ā€“ to the state cell-free DNA screening panel.ā€‹

Turner syndrome

ā€‹Turner syndrome occurs when there is only one X chromosome. Most people either have two X chromosomes (XX) or one X and one Y chromosome (XY).  

Turner syndrome is a genetic condition that can cause mild developmental delays, learning disabilities, heart defects, and infertility. The signs of Turner syndrome are different from one person to another. Some people have no obvious signs. Some pregnancies affected by Turner syndrome can have serious results. For example, miscarriages are more common in pregnancies carrying a fetus with Turner syndrome.ā€‹

ā€‹Klinefelter synā€‹ā€‹drome

Klinefelter syndrome occurs when there is an extra X chromosome (XXY). Most people either have two X  Chromosomes (XX) or one X and one Y chromosome (XY).ā€‹

Klinefelter syndrome, also called XXY, can cause mild developmental delays, learning disabilities, and infertility. The signs of Klinefelter syndrome are different from one person to another. Some people

have no obvious signs.ā€‹

Trisomā€‹ā€‹y X 

Trisomy X occurs when there is an extra X chromosome (XXX). Most people either have two X chromosomes (XX) or one X and one Y chromosome (XY). 

Trisomy X can cause mild developmental delays and learning disabilities. The signs of trisomy X are different from one person to another. Some people have no obvious signs.

XYā€‹ā€‹Y

XYY is caused when there is an extra Y chromosome. Most people either have two X chromosomes (XX) or one X and one Y chromosome (XY).ā€‹

XYY can cause mild developmental delays and learning disabilities. The signs can vary from person to person. Some people have no obvious signs.ā€‹

Recommended resources for X and Y chromosome variations

ā€‹ā€‹ā€‹ā€‹Finding out about certain birth defects

Neural tube defects

The neural tube starts at the top of the head and ends at the bottom of the spine. It is completely formed by five weeks after conception. The neural tube in the fetus becomes the babyā€™s brain and spinal cord.

Birth defects happen when the neural tube does not develop correctly. Neural tube defects are birth defects that involve the brain or spine. The most common neural tube defects are spina bifida and anencephaly.

Spina bifida

Spina bifida is caused by an issue with the spinal cord while a fetus is developing. Each case of spina bifida is unique. A medical expert at a spina bifida clinic is the best resource to provide details.

The range of medical conditions and abilities can vary widely for people with spina bifida. Each person with this condition has their own strengths and weaknesses that no one can fully predict. Some health concerns for people with spina bifida may include: weakness or loss of feeling in parts of the body that are below the opening; difficulty moving their legs with some who are unable to walk; a build-up of fluid on the brain (hydrocephalus); and toileting issues. 

In select pregnancies, surgery may be done before birth to close the opening in the back. In other cases, surgery is done after birth. No matter when surgery is done, there is no way to cure spina bifida.

The condition is best managed by spina bifida medical experts. They work closely with the parents and child to provide the ideal health care plan. Physical therapy, equipment (like braces, walkers, and wheelchairs), and good health care allow people with spina bifida to reach their best outcomes.

Most people with spina bifida have normal intelligence. Yet, some may have learning or social challenges or both. They can get extra help if needed through services like special education or counseling. These services are provided by school systems and state and federal agencies. Many students with spina bifida thrive in school, and adults with spina bifida can work in many different careers and live independently.

Anencephaly

Anencephaly occurs when a fetus is missing a large part of the brain and skull. This condition is a neural tube defect where the top of the neural tube does not close properly. It is caused by low folic acid levels during pregnancy. The neural tube develops into the brain and spinal cord of a fetus. Anencephaly is almost always fatal shortly after birth.

Families affected by anencephaly often say that they want the opportunity to determine how little or how much medical care their fetus or child receives. They also want access to support services and grief counseling as needed.

Recommended resources

Parent support groups

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