Patients with Genetic Issues – Success Stories from IVF with PGT

Preimplantation Genetic Testing (PGT) allows for chromosomal and genetic analysis of embryos during IVF. There are three main types:

• PGT-A (for aneuploidies): Detects abnormalities in chromosome numbers.
• PGT-M (for monogenic diseases): Screens for single-gene mutations in families with known hereditary conditions.
• PGT-SR (for structural rearrangements): Identifies chromosomal abnormalities due to structural changes like translocations.

PGT is typically performed on day-5 or day-6 embryos (blastocysts) by biopsying cells from the outer layer. The embryos are frozen after biopsy and transferred only after results are known. While this approach can help identify viable embryos, it also reduces the number available for transfer due to testing limitations and potential abnormalities.

When PGT is Recommended

According to international reproductive guidelines, PGT-A may be indicated for:

• Advanced maternal age (AMA)
• Repeated implantation failure (RIF)
• Recurrent pregnancy loss (RPL)

Severe male factor infertility

However, the benefits of PGT-A depend heavily on patient profile. It is more effective for those with a good prognosis: younger age, high egg yield, and good embryo development. In lower-yield cases or where limited embryos are available, its benefit may be limited and could reduce chances of transfer.

Clinical Cases

Case 1: 42-Year-Old, Recurrent Miscarriages, Sperm Donor

A single woman in her early 40s with a history of four miscarriages underwent IVF using her own eggs and donor sperm. A strong ovarian response yielded 15 eggs, with 13 mature and 11 fertilized. Five embryos reached blastocyst stage; two tested chromosomally normal. One embryo was transferred, resulting in an ongoing pregnancy and delivery.

Case 2: 30-Year-Old, Severe Male Factor, Recurrent Miscarriages

A younger woman with a history of five miscarriages and a male partner with infertility underwent IVF with PGT-A. Stimulation resulted in 26 eggs retrieved, 21 mature, and 17 fertilized. Nine embryos reached blastocyst stage. PGT-A identified three normal embryos, which led to an ongoing pregnancy after the first transfer.

Case 3: 29-Year-Old, Partner with Genetic Disorder (Marfan Syndrome)

A couple sought PGT-M due to a known genetic condition in the male partner. Stimulation produced 25 eggs, 21 mature, with six reaching the blastocyst stage. Five embryos tested negative for the mutation. One embryo was transferred and four frozen, leading to an ongoing pregnancy.

Case 4: 29-Year-Old, Partner with Chromosomal Translocation

In another case, the male partner carried a Robertsonian translocation, a common structural rearrangement. The couple had four miscarriages. IVF yielded 32 eggs, 29 mature, and 25 fertilized. Seven reached blastocyst stage. After PGT-SR, four embryos were deemed normal. The first transfer resulted in a biochemical pregnancy; the second led to an ongoing pregnancy and birth.

Structural rearrangements like these often justify PGT-SR to avoid implantation failure or loss.

Key Takeaways

• PGT can significantly help identify embryos with the highest chances of success, especially in cases of recurrent loss or genetic risk.
• The number of viable embryos usually decreases throughout the testing process.
• Patients should be prepared for the possibility that no embryos may be suitable for transfer after testing.

Is PGT-A helpful after IVF failures and miscarriage?

PGT-A may be useful when there is a history of poor outcomes and sufficient embryo numbers. It can provide clarity on embryo health, but results may lead to fewer embryos for transfer.

Should PGT-A be done with low ovarian reserve or in embryo banking strategies?

It depends on the number and quality of embryos. PGT-A is only possible at the blastocyst stage, and not all day-3 embryos will reach that point. Embryo banking aims to collect enough embryos for testing and transfer.

Are genetic mutations mainly age-related?

Yes. Egg quality declines with age, increasing the risk of chromosomal abnormalities. Egg donation from younger donors can significantly reduce this risk.

What causes poor embryo development in women under 35?

Even in ideal scenarios, human reproduction is biologically inefficient. Often, no clear cause is found for embryo development issues in younger women.

What’s the main cause of biochemical pregnancies?

For women over 40, genetic issues in the embryo are a leading cause. Endometrial issues can also play a role, though even with optimal conditions, early loss can occur.

Is total fertilization failure a sign of poor egg quality?

If sperm is normal and failure occurs despite ICSI, it can indicate egg-related issues. Even with optimal donor eggs and sperm, complete failure is still possible in rare cases.