NIPT (also called NIPS) is a prenatal screening test that screens for extra or missing copies of chromosomes 13, 18, 21 and the sex chromosomes. PGT-A screens for extra or missing copies all chromosomes, including 13, 18, 21 and sex chromosomes. After PGT-A, your pregnancy is at very low risk for a chromosome condition, but since PGT-A isn’t a perfect test, you can consider NIPT if you want further reassurance. If there are any specific ultrasound findings, NIPT may be suggested by your doctor.

Most likely you have been offered something called “PGT-A,” which is a type of genetic testing anyone can do on their embryos. It stands for Pre-implantation Genetic Testing for Aneuploidy, and it checks the embryo for extra or missing chromosomes before pregnancy. PGT-A is often used to help pick embryos that are more likely to lead to successful pregnancies. But PGT-A does not guarantee a pregnancy or healthy baby. There are many things it can’t detect.

In some cases, a specialized type of genetic testing can be done on embryos. If you or your partner have a specific disease-causing change (i.e. mutation) in one of your own genes, or a rearrangement in your chromosomes, you may be eligible for PGT-M or PGT-SR. Ask your doctor for more information, and to find out if this applies to you.

Our genome, or DNA, is how we refer to the information contained in our cells which provides the ‘recipe’ to create an individual. Exons are the parts of our DNA that provide instructions to create proteins, and they make up  around 1% of our DNA. Proteins are important for our cells to carry out their functions (E.g., helping us grow, digesting our food, keeping our hearts beating). Together, all of the exons in our genome are known as the exome, and the method of sequencing them is known as whole-exome sequencing (WES). This approach to testing looks for genetic changes in exons of all genes. WES is thought to be an efficient method to identify possible disease-causing genetic changes (i.e. pathogenic or likely pathogenic variants, also called mutations) because most known variants that cause disease occur in exons. 

In Canada, an appointment with a genetic counsellor is often covered by provincial health systems for individuals who meet eligibility criteria.  Eligibility can vary from centre to centre. 

Genetic counselling appointments through a private clinic are typically not covered by provincial health insurance plans.  Some extended health insurance plans may cover a portion of a fee for genetic counselling and/or genetic testing.  Some genetic testing companies offer accompanying genetic counselling services.

We can test pregnancies for chromosome conditions, such as Down syndrome. Additionally, we can test a pregnancy for specific genetic conditions if there is a known diagnosis in the family, and that person has had genetic testing. Other conditions would not be tested for in pregnancy unless there was a reason to arrange this testing. For example, if there were specific ultrasound findings. Some diagnoses, such as autism, typically do not have a clear genetic cause, and therefore cannot be checked for in a pregnancy. Targeted genetic testing in a pregnancy is done through an amniocentesis or chorionic villus sampling (CVS).

Genetic counselling is a healthcare service that provides information to individuals and their families about how genetics can impact health. It also involves supporting families as they adapt to new genetic information.

Genetic counselling may help individuals:

• Understand their chances of having a genetic condition
• Understand the chance of having a biological child with a genetic condition
• Understand the features of a genetic condition and how it is passed down (or inherited) in a family
• Make informed decisions regarding family planning, genetic testing, and future health care, based on genetic test results

Usually, genetic counselling is provided by a Genetic Counsellor. Sometimes doctors, nurses, or other health care providers also provide genetic counselling. 

Genetic counsellors often work in a hospital-based genetics clinic. They also work in laboratories, industry, education, and public health settings. 

A formal definition of genetic counselling can be found in this peer reviewed journal article.