Many couples choose to see a genetic counselor before, during or after the pregnancy. Prenatal genetic counselling can help provide answers to questions about possible genetic disorders. This procedure is an important part of monitoring the pregnancy.
Most couples meet a genetic counselor before conceiving, as part of prenatal screening tests. In addition, many couples are referred to genetic counselling during the pregnancy after abnormal screening test results that may indicate a risk for genetic disorders.
Newborn screening is offered after birth when the baby’s screening results show a possible risk for a genetic disorder, or when the baby shows signs of diseases related to a genetic disorder. In these cases, parents are referred to genetic counselling for different infant screening tests.
What happens in genetic counselling?
Prenatal genetic counselling is usually offered at genetic institutes or prenatal treatment centers. The counselling begins with a meeting in which the counselor will ask the couple about family medical history. These details may include different illnesses that run in the family, ethnic descent and significant events that may be related to genetic disorders.
After this initial meeting, the genetic counselor examines the data, analyzes tests results, and explains the importance and meaning of these results to the parents-to-be. The counselor may then recommend further genetic testing when these are required.
The following course of action usually includes extensive genetic testing, amniocentesis, chorionic villus sampling (CVS), maternal blood screening, etc. In more complex cases, couples are referred to a geneticist – a health care provider who can give a medical opinion and provide advice and guidance according to their extensive experience.
When is genetic counselling recommended?
Prenatal genetic counselling is offered whenever a risk for genetic disorders arises. It is mainly recommended in the following cases:
The couple have genetic disorders
If one of the partners has a known genetic disorder, the couple is referred to genetic counselling for guidance. If both partners have a certain genetic disorder (a known condition or a disorder diagnosed during preconception testing), they will be referred to genetic counselling who will help them understand the risks and options.
consanguineous marriages
When partners are closely related family members, genetic counselling is required to test carrier status to different gene mutations. Consanguinity is known to increase the risk of genetic disorders. For this reason, consanguineous couples should undergo genetic counselling prior to every pregnancy.
Having a child with a genetic disorder
When couples have a child with a known genetic disorder, they will undergo genetic counselling to determine if one of them is a carrier of that disease. In these cases, genetic counselling plays an important part in planning future pregnancies.
In addition, when a child suffers from an unknown disorder, genetic counselling can help determine of there is a genetic basis to this condition. Families in these situations are usually referred to a geneticist in addition to seeing a genetic counselor.
Abnormal prenatal test results
The most common reason couples are referred to genetic counselling are abnormal prenatal test results. These tests include first trimester maternal blood screening, nuchal translucency tests, alpha-fetoprotein test (triple test), anomaly scan, fetal wellbeing ultrasound, and more.
When these test results are abnormal, couples are referred to genetic counselling to help make decisions about more extensive diagnostic testing. These tests may include chorionic villus sampling, amniocentesis, fetal ultrasound, and more.
The importance of genetic counselling
Genetic counselling is highly important and should not be given up when required. Counselling can help couples get the most up-to-date information relevant to their situation. It can also provide solutions to the genetic disorder; couples can choose to undergo further diagnostic tests and procedures such as PGD (Preimplantation genetic diagnosis) that is offered to those undergoing IVF.
Ultimately, prenatal genetic counselling has an important role in ensuring a healthy pregnancy. Thanks to genetic counsellors, the prevalence of genetic disorders in the population is currently declining.