PGT-A Reduces Miscarriage Risk: What Patients Should Know

When you have decided to undergo IVF, your biggest desire would be to get pregnant after embryo transfer. However, that’s not the only concern aspiring parents have. What actually matters is a healthy pregnancy that completes the term (9 months of gestation). Miscarriages are more common than you think, particularly in couples undergoing IVF who have a history of miscarriages. 

Many factors can contribute to the heightened risk of miscarriage, but the most common among these is a chromosomal defect in the embryo. That’s where Preimplantation Genetic Testing for Aneuploidy, or PGT-A in Pakistan, steps in. It’s a preimplantation genetic testing tool that examines the embryo for quality and chromosomal abnormalities. In this post, we’ll explore PGT-A in detail, why it matters, and the benefits.

What is PGT-A?

For the embryo to implant successfully into the uterine lining after transfer, it must have the correct set of chromosomes, a total of 46 (23 pairs). If the embryo is euploid, it has proper chromosome sets and is likely to be implanted into the uterus without the risk of miscarriage due to chromosomal defects.

Understanding Aneuploidy

A report by the Cleveland Clinic shows that 1 in every 150 pregnancies is affected by chromosomal defects, and around 50% of these pregnancies end in miscarriage. 

Aneuploidy is a chromosomal defect in the embryo. An embryo is considered aneuploid if it has too few or too many chromosomes, resulting in an abnormal pair of chromosomes. This can lead to miscarriage in early pregnancy.

For example, an extra copy of chromosomes, such as 47 cells instead of 46, is called trisomy, while a missing pair of chromosomes is called monosomy. This could happen if the eggs or sperm do not form properly. Let’s understand each type of aneuploidy in brief.

Trisomy 21

Also called Down Syndrome, Trisomy 21 occurs when there’s an extra copy (making it three) of chromosome 21. It’s not a genetic disease, but rather a birth defect that results from improper cell division. Down Syndrome is the most common type of chromosomal defect in children. It can result in developmental delays, distinctive facial features, heart issues, thyroid problems, gastrointestinal conditions, etc.

Trisomy 18

Trisomy 18 is when a child has an extra copy of chromosome 18. The condition is called Edwards Syndrome, and babies born with this chromosomal defect are likely to experience serious heart defects, developmental delays, and other growth-related challenges. Most pregnancies with this chromosomal defect end in miscarriage. Even if the pregnancy is carried to term and the baby is delivered, the survival rates are extremely low.

Trisomy 13

Patau Syndrome, also known as Trisomy 13, occurs when a baby has an extra copy of chromosome 13. Like Edward Syndrome, survival rates in babies with Trisomy 13 are low. These babies, if born, might have cleft lip, heart abnormalities, and brain issues.

Monosomy X

Monosomy X, also known as Turner Syndrome, is another chromosomal defect in which female babies have a single X chromosome instead of the typical two. With proper treatment, survival is possible, although these women are at increased risk of infertility and delayed puberty due to their underdeveloped ovaries. 

Benefits of PGT-A

Preimplantation Genetic Testing (PGT) is a screening test conducted during IVF to identify the healthiest embryos for transfer. Through this screening, embryos produced during IVF are carefully examined to ensure that they have proper chromosomal makeup and are free of genetic diseases. 

PGT is classified into three types, each of which checks the embryo’s chromosome structure. They include PGT-A, PGT-M (monogenic), and PGT-SR. Among these, PGT-A is commonly used to test the embryo for chromosomal defects, so that a healthy embryo can be selected for IVF. Let’s take a look at the benefits of PGT-A:

Identifying Chromosomal Defects: The test helps separate embryos with abnormal pairs of chromosomes from those with healthy pairs. This reduces the number of IVF cycles a person has to go through. An embryologist can use an embryo with no visible chromosomal abnormality. This can improve the success rate of implantation after embryo transfer.

Reduces Miscarriage Risk: Now that the embryo transferred is overall healthy and has normal genetic material, it’s likely to implant successfully and result in a healthy pregnancy. Simply put, PGT-A significantly reduces the risk of miscarriages that occur because of defects in chromosome structure or count.

Increase Live Birth Rates: Research shows a live birth rate of 57% per embryo transfer in women who underwent PGT-A. Since it reduces the risk of miscarriage, it helps increase the likelihood of the pregnancy reaching full-term and resulting in the birth of a live, healthy baby.

Save Time, Cost, and Mental Stress: With the healthiest embryo transferred to your uterus, you can rest easy knowing that there’s a good chance the embryo will successfully implant and you won’t need to undergo more IVF cycles. This not only saves you the mental and physical exhaustion, but also the cost and time you’d spend on repeated IVF cycles.

Who Should Consider PGT-A?

This leads us to a question: who should consider this genetic testing before IVF in Lahore? PGT-A is an optional procedure, but is highly recommended for couples with:

Recurrent MIscarriages: If you have a history of recurrent miscarriages, you may want to consider getting this preimplantation genetic test. It helps choose euploid embryos, which might transfer successfully into the uterus.

Women Over 35: Complications in fertility increase with age. Your egg quality starts diminishing, and the risk of chromosomal abnormalities increases. If you are above 35 and considering IVF, a PGT-A test can select embryos that have the normal number of chromosomes, thus giving you peace of mind and a chance at a healthy pregnancy.

Multiple Failed IVF Cycles: An IVF cycle can fail for many reasons, one of which is chromosomal defects in the embryo. PGT-A helps rule out chromosomal issues in the embryo as the potential cause of failed IVF cycles. 

History of Chromosomal Defects: Women with a history of pregnancies affected by Down, Edward, Turner, and Patau Syndrome can have PGT-A to ensure the chromosomal abnormalities do not affect their existing pregnancy.

Step-by-Step: How PGT-A is Done

IVF starts with ovarian stimulation, which prepares your ovaries to release multiple eggs for retrieval. These eggs are surgically aspirated after the trigger shot. The retrieved eggs are fertilized with sperm in a controlled environment. These fertilized embryos are then kept in an incubator that mimics the woman’s womb. 

Biopsy: Once the embryo reaches the blastocyst stage, i.e,. When the embryo turns into a ball containing 100-200 cells, the embryologist takes a sample of these cells from the outer layer, which will eventually form the placenta. It’s carried out carefully so that the cells that will form the baby remain unharmed.

Freezing: The embryos are frozen through a process called vitrification, unless the PGT is done and the results are available.

Genetic Analysis: The sample cells collected in the biopsy are sent to the lab for proper screening. They are screened for chromosomal abnormalities with next-gen sequencing.

Transfer: Once the results are in, your fertility specialist reviews the results and selects the healthy embryos that are euploid and transfers them into your uterus through a quick and painless procedure. After transfer, you are advised to wait 2 weeks before taking a home pregnancy test.

Limitations & Ethical Considerations

Although PGT-A has helped many couples in delivering a healthy baby, it may not work for everyone. Here’s what you should know.

It Doesn’t Guarantee Pregnancy

PGT-A makes pregnancy more likely in women who have had repeated miscarriages or IVF failures because of chromosomal defects. However, it doesn’t promise live birth for everyone undergoing IVF. A successful implantation requires a proper uterine lining and a healthy mother. Sometimes, even euploid embryos might not implant because of other health issues.

Cost Factor

The cost of PGT-A in Pakistan is generally not included in the IVF package. Since it’s optional, you will have to pay for it separately. The IVF package is already pretty expensive. Having another screening test can push the total cost even higher. 

False Results

Some embryos have a mix of normal and abnormal cells (mosaic embryos). The cells collected in a biopsy might not represent the entire embryo, leading to false results. For example, if the part used for screening looks abnormal, the entire embryo might be marked as “abnormal”. In reality, there’s a possibility that the inner cells (that will actually form the baby) can be normal.

Risk to the Embryo

Biopsy and PGT-A are done carefully, ensuring that the embryo itself doesn’t get harmed. However, it does carry a small risk that the embryo may not survive the procedure.

PGT-A at Australian Concept 

PGT-A is an advanced IVF tool that has shown promising results in patients who’ve experienced repeated miscarriages or other birth issues in babies due to poor formation of chromosomes. Some certified fertility labs in Pakistan, such as Australian Concept, offer PGT-A to help couples conceive successfully. 

The fertility center has over 15 branches, each equipped with state-of-the-art technology and internationally certified fertility specialists. If you are planning to start IVF, discuss PGT-A with your doctors in ACIMC to reduce your risk of implantation failure or miscarriage.