Pre-Implantation Genetic Diagnosis PGD Test for IVF

by Geetanjali Kapoor Medical Content Writer

Do you have a history of recurrent miscarriages, repeated IVF failure, or a previous child with a genetic disorder? Also, do you or your partner carries chromosomal translocations or single gene disorder? If yes, then the PGT test solves all your worries! This test helps you to be a proud mother and father of a healthy kid.

Pre-implantation genetic diagnosis is used in the IVF cycle to enhance the potential for successful delivery and pregnancy. It is a testing technique performed on the cells removed from embryos to avoid genetic disorders. Also, specialists recommend going for a PGT test to ensure that the embryo selected for transfer has the right number of chromosomes, thereby decreasing the chances of miscarriage and failed IVF cycle.

Females over 37 years of age who want to conceive and couples with a higher probability of having a kid with an inherited genetic disorder may opt for a PGT test. There are broadly two types of tests that are discussed below:

PGT testing for monogenic disease

PGT-M screens specific gene mutations carried by either of the parents. A genetic disorder increases the probability of a child being born with genetic mutations leading to the development of various illnesses. Hence, it can analyze various chromosomal abnormalities like trisomy, Down’s syndrome, monosomies, sickle cell anemia, cystic fibrosis, and sex chromosomal abnormalities.

PGT test for chromosome structural rearrangement (PGT- SR)

PGT-SR detects embryos with chromosomal structural rearrangements like translocations or inversions. Patients with this type of defect are at risk of producing embryos having a chromosomal defect leading to an increased risk of repeated miscarriages. This PGT test for IVF can examine disorders like Robertsonian, Non-reciprocal, and Reciprocal translocations.

How is the PGT test conducted?

IVF treatment is done to obtain embryos for PGT. After the lab's retrieval and fertilization of eggs, embryologists conduct assisted hatching to obtain the cells for screening. A few cells outside the embryo are biopsied and sent for genetic analysis after reaching the blastocyst stage. Then the specialist analyses the condition accordingly.

Advantages of the PGT test

Improved selection of embryos The embryos without abnormalities can result in the birth of a healthy child. This test helps to select normal embryos and rule out the ones with genetic disorders.
Avoid transferring embryos that will not implant- The chromosomal abnormalities prevent embryos from developing in the initial stages and the implantation in the mother’s uterus. The test support identifying these kinds of embryos and selecting the healthy one for implantation.
Avoid embryo transfer resulting in the birth of children with syndrome or loss of a pregnancy- Certain genetic abnormalities are less harmful, enabling the implantation of the embryo but resulting in loss of pregnancy or child death due to the presence of various syndromes like Patau’s syndrome, Down’s syndrome, and Edwards’ syndrome. The pre-implantation genetic diagnosis rules out these types of genetic conditions.
Reduces time required to get pregnant- The timely screening helps to save a lot of time as we can identify which embryo can result in full-term pregnancy. Hence, the diagnostic test allows couples to have healthy babies.

Limitations of PGD testing in in-vitro fertilization

The wrong interpretation of the result can lead to the transfer of the defective embryo into the uterus.
The PGT test can’t detect all genetic diseases and cannot eliminate the risk.

Takeaway points

Pre-implantation genetic diagnosis is an extra step in the IVF procedure as it reduces the risk of failed transfers and miscarriage. The test analyzes genetic abnormalities in the embryo before it transfers to the mother. The key purpose is to ensure that kids born are healthy without any genetic disorders.