Protecting families with preconception genetic screening
Both the American Congress of Obstetricians and Gynecologists and the American College of Medical Genetics recommend that all couples considering pregnancy undergo preconception genetic screening for genetic diseases. By undergoing screening before pregnancy, men and women can learn whether they carry any inheritable diseases that could be passed to their children. Our San Antonio fertility specialists can use this information to recommend fertility treatments that can prevent parents from transmitting these diseases to their children.
Understanding the need for preconception genetic screening
All genetically normal individuals have 46 chromosomes; they received 23 from their mother and 23 from their father. Each chromosome contains hundreds or even thousands of smaller segments of DNA called genes. While most miscarriages are caused by an abnormality in chromosome number -ie. an embryo with more or less than 46 total chromosomes, most genetic disorders are caused by a defect in the DNA that makes up a specific gene.
- In order to be the most common type of genetic disease (called an autosomal recessive disorder), an individual must inherit a defective copy of the gene from both parents.
- Individuals who inherit one defective gene (from one parent) and one normal gene (from the other parent) are called carriers, and they typically do not have symptoms of the disease.
- A classic example of an autosomal recessive disorder is cystic fibrosis. In this condition, individuals with two abnormal genes suffer from this life threatening disorder, while individuals with only one abnormal gene (“carriers”) typically never have symptoms and usually lead a normal life.
Many genetic disorders follow a specific mode of inheritance. If one parent who is a carrier has a child with another carrier, there is a 50% chance that their baby will also be a carrier (and therefore unaffected by the disease) because it received one normal gene from one parent and one abnormal gene from the other parent). There is a 25% chance their baby will be affected (because it inherited one abnormal gene from each parent), and a 25% chance their baby will be unaffected (because it inherited one normal gene from each parent).
It can be difficult to determine whether a person carries a genetic disease because many times carriers do not have either symptoms or a family history of the disease. A carrier may even have other children who are healthy. Our San Antonio fertility specialists offer preconception genetic screening that can help determine whether you or your partner are carriers of a specific genetic disorder and thus can help reduce the risk of passing the disease to your children.
The preconception genetic screening process
Through preconception genetic screening, you can learn whether you and your partner are carriers of a genetic disease. Genetic testing, or “carrier screening”, involves a simple, affordable test that can be performed using your blood or saliva. Your test results will arrive in one to two weeks. Once your San Antonio fertility specialist receives the results, they will review them with you and help you determine your best treatment plan.
If our San Antonio fertility specialists find that you and your partner are both carriers of a genetic disorder, then in vitro fertilization, or IVF, may be recommended. Embryos created through IVF can be screened for this disease prior to transferring them into the uterus. This technology allows our fertility specialists to transfer only genetically normal embryos, essentially eliminating the risk that the genetic disorder will be passed to your children.
Preconception genetic screening gives men and women the best chance of having a healthy child. Contact us to learn more about genetic testing.
Learn More About Infertility With TFC Videos
Dr. Erica Munch Talks About Fertility Testing