The Role of Genetic Testing in IVF
IVF, aka in-vitro fertilization, has become the popular treatment for couples who are unable to conceive naturally. It involves extracting eggs, retrieving a sperm sample, and then manually combining them in a laboratory dish to create an embryo. This embryo is then transferred to the uterus for pregnancy. The procedure seems very simple, but it comes with hope, patience, and, sometimes, uncertainties. That’s where genetic IVF testing steps in, promising to increase the chances of success.
So, if you are considering IVF treatment, keep reading the blog. In this blog, we will discuss what genetic testing is and its role in IVF treatment.
What is Genetic Testing?
Let’s start with the basic term: genetic testing.
In simple terms, genetic testing examines your DNA, the chemical database that carries instructions for your body’s functions. As you age, chances are there that changes can occur in DNA. Genetic testing can reveal these changes that may cause disease.
Integrating genetic testing into IVF treatment adds a high-tech layer to the delicate procedure. After egg retrieval and fertilization, the resultant embryos are genetically screened. This screening checks for specific genetic disorders or the overall chromosomal normality.
Importance of Genetic Testing in IVF Treatment
For couples seeking IVF, genetic testing offers a powerful tool to boost their chances of a healthy baby. This advanced technique analyzes embryos for chromosomal or genetic abnormalities before they are transferred to the uterus, allowing you to choose the healthiest one for implantation. By prioritizing the most promising embryos, genetic testing can significantly increase your chances of a successful pregnancy and minimize the risk of miscarriage or congenital disabilities. How does genetic IVF testing help?
Aneuploidy Screening: Genetic composition plays a more significant role in fertility with age. One crucial aspect is aneuploidy, an abnormality in the number or structure of chromosomes. In women, with age, the quality of eggs may decline, leading to a higher risk of producing embryos with chromosomal abnormalities. These genetic variations can cause fertility issues and miscarriage, making natural conception more challenging.
Similarly, in men, especially after the age of 40-45, the quality of sperm can deteriorate, increasing the chance of genetic errors.
Here, preimplantation genetic testing comes into play. It helps fertility doctors at the best IVF centre in Delhi to select embryos with the correct chromosome number, increasing the likelihood of a successful pregnancy.
Single Gene Disorder Screening: Single gene disorders, as the name suggests, result from mutations in a specific gene, such as cystic fibrosis, sickle cell anemia, and Huntington’s disease. Genetic IVF testing can help to ensure embryos selected for transfer are free from these specific genetic conditions, thus preventing their transmission to the child.
Detection of Genetic Blood Disorders: Thalassemia is a common genetic blood disorder. When both partners are carriers, there’s a 25% chance their child will be affected. But thanks to preimplantation genetic testing. It enables doctors or embryologists to identify the embryos free from thalassemia, ensuring a healthy pregnancy and significantly reducing the risk of transmission.
Mosaicism Detection: Mosaicism occurs when a person, or in terms of IVF treatment, an embryo, has two or more different cell types, each with a distinct genetic profile. This means some cells may have the usual number of chromosomes while others may have abnormalities.
Mosaicism can affect IVF outcomes. While some mosaic embryos can develop into healthy babies, others may lead to implantation failures, miscarriages, or, in rare cases, congenital disabilities. In order to avoid these, preimplantation genetic IVF testing can help make an informed decision on selecting a healthy embryo.
How Does Genetic Testing Work?
Here comes the most interesting part: how does genetic testing in IVF treatment work?
Preimplantation genetic testing can be categorized mainly into three types: PGT-A (for aneuploidies), PGT-M (for single-gene disorders), and PGT-SR (for structural rearrangements).
The journey of PGT begins with the standard IVF treatment, where eggs are fertilized in the lab to create embryos. Around the fifth day after egg retrieval, when the embryos reach the blastocyst stage, a few cells are gently extracted from each embryo through biopsy. It is a delicate process, requiring skilled embryologists to ensure the embryo’s health. These cells are then sent for genetic analysis.
The biopsied cells undergo comprehensive genetic analysis using techniques such as Next-Generation Sequencing (NGS), Comparative Genomic Hybridization (CGH) or Polymerase Chain Reaction (PCR).
Next-Generation Sequencing (NGS): NGS or next-generation sequencing is a revolutionary technology that allows for the rapid sequencing of large amounts of DNA or RNA. Unlike traditional sequencing techniques, which reads DNA fragments one at a time, NGS can analyze millions of fragments simultaneously, quickly generating vast amounts of data.
Benefits of NGS in preimplantation genetic IVF testing? It helps to analyze the entire genome of an embryo, revealing all genetic variations, and it is ideal for identifying potential genetic disorders and selecting the healthiest embryos for implantation. NGS can detect abnormalities that can lead to miscarriage or cause serious health problems in the child.
Comparative Genomic Hybridization (CGH): CGH is a powerful genetic tool to detect chromosome numbers and structure imbalances. In this technique, selected DNA is compared with a reference DNA, both labelled with different fluorescent dyes. When mixed on a slide, these DNAs hybridize, or bind, to their complementary sequences. A scanner then analyzes the fluorescence intensity.
What are the benefits of CGH in preimplantation genetic IVF testing? It helps to identify aneuploidy, an abnormal number of chromosomes, like trisomy 21 (Down syndrome) or monosomy X (Turner syndrome). Also, it helps to determine structural changes like deletions, duplications, or translocations in chromosomes that can affect several genes and potentially lead to developmental problems.
Polymerase Chain Reaction (PCR): PCR is a revolutionary technique used to make many copies of a specific DNA segment, especially when only a small amount of DNA is available for testing. In this process, a particular DNA segment is taken and repeated heating and cooling cycles are done to separate DNA strands, bind primers, and synthesize new DNA strands.
The benefits of PCR in genetic IVF testing? PCR can be used to diagnose specific genetic conditions, like cystic fibrosis or sickle cell anemia, in embryos before implantation. This allows couples with a family history of such conditions to select unaffected embryos for transfer, increasing their chances of a healthy pregnancy.
PCR can double-check potential abnormalities detected by other techniques like CGH, providing greater confidence in the diagnosis before making critical decisions.
Selecting and Freezing Embryos
Once the genetic tests are completed, healthy embryos are marked and frozen. These genetically chosen embryos are then used for transfer in a Frozen Embryo Transfer cycle. The embryos after genetic testing are individually frozen and then warmed before transfer when the lining is ready.
This technique is particularly beneficial for couples with a history of genetic diseases, recurrent miscarriages, or older couples who face higher risks of chromosomal abnormalities.
This flexibility of freezing and thawing allows for multiple IVF attempts or future pregnancies using the same batch of embryos.
Addressing Ethical Considerations
While genetic testing can help to determine and prevent passing genetic disorders, like any advanced medical procedure, it raises ethical concerns. Concerns range from the potential for selecting ‘desired’ traits or like identifying the sex of the baby. ( Illegal in India)
It’s a delicate balance between medical advancement and ethical duty. The key lies in balanced, controlled approaches and ongoing moral conversation. Therefore, choosing the best IVF centre in Delhi following all the ethical considerations to avoid legal issues is essential. Also, the best IVF centre can help you to achieve the best outcome in the first IVF cycle.
Conclusion!
Genetic IVF testing isn’t just a scientific advancement; it’s a ray of hope for many aspiring couples. It offers a clearer path through the complex IVF journey, reducing uncertainties and enhancing the chances of a healthy pregnancy.
If you are dealing with infertility and looking for an effective treatment, schedule your consultation with Dr Rhythm Gupta, an experienced infertility specialist in Delhi. She will assess your condition and reason for infertility and find the most effective treatment solution. So, don’t wait to consult with Dr Rhythm and achieve your dream of being a parent.
