IVF With Pre-implantation Genetic Testing (PGT)

IVF with Preimplantation Genetic Testing (PGT)

Selection of the most appropriate embryo to be transferred to achieve a healthy live birth through in vitro fertilization treatments is one of the most important steps of assisted reproductive techniques. Achieving higher rates of healthy live births has become possible, especially by improving the selection criteria of the embryos to be transferred. With Preimplantation Genetic Tests (PGT), it is possible to identify embryos with healthy chromosome structures and prevent unnecessary embryo transfer that may result in implantation failure or miscarriage.

What is Preimplantation Genetic Testing (PGT)?

Preimplantation genetic testing (PGT) is a technique in which one or more cells are taken from an embryo (fertilized egg) for testing to have information about the genetic make-up of the embryo. It is done in a lab and used in conjunction with in vitro fertilization (IVF).

PGT is a new term in fertility medicine that replaces the more familiar terms of preimplantation genetic diagnosis (PGD) and preimplantation genetic screening (PGS), while serving the same functions as those screenings.

Preimplantation genetic testing has three types of screenings as listed below.

• PGT-A (Abnormal chromosome pair number): PGT-A determines whether the embryo has the correct sequence or number of chromosome structures, either one less or one extra (called aneuploidy). Aneuploidy can cause conditions such as trisomy 21, or Down syndrome, and is a strong indicator of birth defects or miscarriage.
• PGT-M (Single genetic/monogenic): PGT-M tests for a single genetic (monogenic) defect or mutation, like cystic fibrosis, BRCA1, muscular dystrophy, Huntington’s disease and Fragile-X syndrome.
• PGT-SR (Structural rearrangements): PGT-SR tests for chromosome structure rearrangements, which often cause recurrent miscarriage and embryos with improper chromosomes, and also greatly decrease the chance of live birth.

When to Consider Preimplantation Genetic Testing (PGT)?

Preimplantation genetic testing (PGT) screens embryos created through in vitro fertilization (IVF) for genetic and chromosome abnormalities before they are transferred to the uterus. For this reason, PGT increases the chance of IVF success and the probability of having a healthy baby.

Preimplantation genetic testing can be considered if;

• One of the partners has or is a carrier of serious inherited disorders to decrease the risk of passing the disorder onto their child
• Previous early birth or abortion of an embryo with a chromosomal abnormality
• Repeated unsuccessful IVF cycles
• Recurrent miscarriages
• Advanced female age (as the risk of chromosomal abnormalities (called aneuploidy) in embryos increases for patients over 35)
• Genetic disorders linked to the gender of the embryo

Sex selection allows couples to prevent the transmission of sex-linked genetic disorders such as hemophilia, muscular dystrophy and fragile-X syndrome and to choose female or unaffected male embryos in order to prevent the risk of these genetic disorders in their children.

Family Balancing

Patients may be interested in selecting the sex of their child to “balance” the number of girls or boys in their families.

Sex selection, also known as gender selection or family balancing, is the process of determining the gender (male or female) of each embryo created through in vitro fertilization (IVF).

The gender identification of embryos is done using preimplantation genetic testing (PGT), which involves taking a few cells from an embryo on the 3rd or 5th day after embryo creation, and determining the sex of the embryos through genetic analysis.

After testing, only the healthy embryos are implemented to woman’s uterus during an embryo transfer procedure.

How is the IVF treatment process with Preimplantation Genetic Testing (PGT)?

1 - Consultation

Your IVF journey begins with a consultation with one of our fertility experts, where we’ll discuss and assess your fertility status by reviewing your and your partner’s most recent blood tests and health reports and creating a customised plan for you.

2. Ovarian stimulation phase

• Once we pass this stage and have a clear profile of your status and medical history, our fertility specialist will prepare your medication protocol.
• You'll start your ovarian stimulation phase from the 2nd day of your menstrual cycle and continue for approximately 10-14 days. During this phase, you'll take stimulation medicines and injections from our medical team with multiple ultrasound checkups to monitor your ovaries’ progress.
• Once our doctor confirms the follicles have reached the targeted size, the stimulation phase ends, and you are prepared for the egg retrieval procedure. We will inform you about the exact timing of the trigger injection to help release the eggs.

3. Egg Retrieval

• When the eggs are mature, the stimulation phase ends, and you undergo the egg retrieval procedure.
• The egg retrieval (OPU) procedure is performed using sedation (anaesthesia) at our hospital, which takes approximately 15-20 mins.
• After the egg retrieval procedure, you will be informed about the number and quality of eggs collected.

4. Fertilization

Our embryologists fertilise the collected eggs with your partner’s sperm. We use the ICSI method for the fertilisation procedure, injecting the selected sperm directly into the egg.

5. Preimplantation Genetic Testing (PGT)

After fertilisation, the embryos will be kept in a particular culture medium in the laboratory for five days. Following embryo creation, preimplantation genetic testing will be performed on 3rd or 5th day by taking a biopsy from each embryo.

• PGT-A with FISH technique can be used for discovering common abnormalities on such chromosomes 13, 15, 16, 17, 18, 21, 22. The FISH technique is also one of the methods used in gender determination (chromosomes X, Y).
• Next Generation Sequencing (NGS) is a newer technology that has been used for preimplantation genetic testing. Compared to FISH tecnique, NGS method is a more comprehensive chromosome analysis method applied to all (23 pairs of) chromosomes of the embryos, and it allows early detection of chromosomal (structural or numerical) abnormalities. The test is done on the cells (biopsy) taken from the embryos in the early blastocyst stage - the 5th day of development. With NGS techique, it is also possible to identify the gender of the embryos.

6. Embryo Transfer

The healthy and highest-quality embryos are selected and transferred into the uterus at the end of the laboratory process. The number of embryos to be transferred is decided by our doctor with you, considering your age, general health, previous unsuccessful IVF attempts and the quality of the embryos. (If more than one embryo is transferred, the possibility of multiple pregnancies increases.) Based on the regulation in North Cyprus, we are allowed to transfer a maximum of three embryos at one transfer.

7. Embryo Freezing

After one or two healthy embryos are transferred into the uterus, the remaining embryos are frozen for future use on the same day of embryo transfer.

8. Pregnancy Test

In this way, your IVF cycle is completed. You will perform a pregnancy blood test after 12 days after the embryo transfer date and let us know the result.