In most cases, pregnancy is a joyous time filled with wonder and excitement for the future. But it can also stir up feelings of anxiety as parents worry about the health of their unborn child. Olivia McMillan, genetic counselor, Advanced Perinatal Care Center, Parkview Health, discusses prenatal genetic counseling and what parents can expect during a counseling appointment.
What is prenatal genetic counseling?
Prenatal genetic counseling is helpful when individuals and/or families are at an increased risk of having a child with a birth defect or genetic condition. Prenatal genetic counselors typically see patients who are currently pregnant or considering becoming pregnant in the future.
Why should someone seek the services of a prenatal genetic counselor?
You should consider consulting a prenatal genetic counselor if:
- You have a personal or family history of a genetic condition such as fragile X syndrome, cystic fibrosis or sickle cell anemia.
- You have a personal or family history of birth defects such as a heart defect or cleft lip/palate.
- You have a previous child with a genetic condition, birth defect, or developmental/intellectual concern like delayed walking and talking or abnormal height and weight compared to peers.
- You are pregnant or plan to become pregnant after the age of 35.
- You have a history of infertility, stillbirth or miscarriages (three or more).
- You take medications/drugs or come in contact with a chemical or virus that may impact the baby.
A provider may also refer someone to a prenatal genetic counselor if they discover any ultrasound irregularities or screening abnormalities during pregnancy. The genetic counselor will help explain any medical information, what to expect, how to prepare and management options moving forward.
What happens during a prenatal genetic counseling appointment?
The primary goal of a genetic counseling consultation is to advocate for the patient and family while helping them understand the medical and genetic information being presented to them so they can make an informed decision about their care. During an appointment, a prenatal genetic counselor will take a detailed family and pregnancy history, discuss any relevant screening and testing results, review and explain ultrasound findings and discuss possible options for pregnancy management moving forward. All these efforts combined will allow the genetic counselor to provide a patient-specific risk assessment for genetic conditions, birth defects, prescribed medication, drug or alcohol exposures. If you haven’t had any genetic screening or testing done, the genetic counselor will explain and facilitate decision-making regarding your options before, during and after pregnancy.
What is the difference between prenatal diagnostic genetic testing and prenatal genetic screenings?
Prenatal diagnostic genetic testing helps identify or rule out genetic disorders. Most providers recommend prenatal diagnostic genetic testing to individuals or families who want to know more about the risk of a specific condition. There are two options for prenatal diagnostic testing, including chorionic villus sampling (CVS) and amniocentesis. CVS testing is typically performed at 10-13 weeks of pregnancy, whereas amniocentesis can occur after 16 weeks. Genetic counselors can help explain the benefits, potential risks and limitations of either genetic test.
Prenatal genetic screenings, on the other hand, are not diagnostic. While screenings can provide important information regarding a baby’s risk of developing a disorder or condition, they are not conclusive. Only a diagnostic test can definitively identify if an infant has a birth defect or genetic disease. With that said, there are four main types of genetic screenings that can take place during pregnancy. They include maternal serum screening, non-invasive prenatal screening (cell-free DNA screening), carrier screening and an ultrasound screening.
What do the results of prenatal screenings mean?
Prenatal screenings help assess your child’s risk of developing a genetic condition or disorder. Most screenings will help indicate whether your child is:
- Low risk (normal): There is a lower-than-average risk that your baby may have any of the screened for genetic conditions.
- High risk (abnormal): There is a higher-than-average risk that your baby may have a genetic condition. Typically, the screening will also specify which condition they are at risk of developing.
Remember, genetic screenings are not diagnostic, and it’s possible to have both false positive and false negative results during pregnancy. Screenings can’t diagnose a baby with a genetic condition. Instead, they are used to identify pregnancies that may be at a higher risk, similar to breast cancer screenings for at-risk individuals.
Final thoughts
If you feel that you may need the services of a prenatal genetic counselor, please speak with your primary care provider or obstetrician about a possible referral to the Parkview Advanced Perinatal Care Center, or visit the National Society of Genetic Counselors to find a genetic counselor near you.
