Since 1990 it is possible to genetically test embryos before they are transferred to the uterus! This method is known as Preimplantation Genetic Diagnosis (P.G.D) and is a reproductive technology that offers couples, at high risk of transmitting a genetic disorder to their future offspring, a valuable diagnostic tool.

Preimplantation Genetic Testing can be used to test for:

Diagnosis of monogenic disorders has helped couples where both partners are carriers of the defective gene for a specific genetic disorder (e.g. a or b-thalassemia).

Few of the most frequently diseases diagnosed by PGD are:

Testing for chromosomal abnormalities involves either numerical disorders or structural abnormalities. It is known that the incidence of chromosomal abnormalities (e.g. Down syndrome) increases with maternal age.

However, there are also other factors, than maternal age, contributing to structural chromosome abnormalities (chromosomal inversion or translocation).

It is common to find in couples that one or both partners are carriers of a chromosomal abnormality (not necessarily the same). This abnormality, not expressed in parents, may cause recurrent miscarriages or repeated IVF failure. Preimplantation Genetic Screening (P.G.S) can diagnose chromosomal abnormalities and protect the couple from the emotional distress or somatic burden caused by recurrent miscarriages or repeated IVF failure. Moreover, time and money are saved.

The terms Preimplantation genetic diagnosis (PGD) and screening (PGS) have been replaced by Preimplantation genetic testing (PGT).

These include: PGT for aneuploidies (PGT-A)
PGT for monogenic/single gene defects (PGT-M)
PGT for chromosomal structural rearrangements (PGT-SR).

PGT has been used for:

Lately Next Generation Sequencing (NGS) is the new technology for comprehensive chromosome testing of IVF embryos. Next Generation Sequencing for PGT is likely going to replace other technologies as the predominant method for testing due to lower cost and reduced errors.

According to experience with PGT, a successful program involves the interaction between doctors, clinical embryologists, pshycologists and geneticists. It is also very important for the couple to receive proper genetic counseling prior to PGT.

Couples having PGT should go through Assisted Reproductive Technologies, even in the absence of infertility. ART is the only way to produce the embryos to be tested, outside the woman’s body. The early embryo (6 to 8 cells on day 3 of development) is biopsied by microsurgical removal of 1 to 2 cells. Some embryologists wait until the embryo reaches the blastocyst stage (day 5 of development) to undertake this biopsy. At this stage more cells can be removed and analyzed. Once collected, these cells have to be analyzed for detection of a certain medical condition. Their genetic material is the same as of the embryo they originated from. In all these procedures, analysis must be completed soon (1-2 days after biopsy). Embryo selection is based on diagnosis. Only healthy embryos can be successfully transferred, with high safety and success rates.

According to recent studies when a couple is not able to conceive over a period of 3 years, the chances to get pregnancy in the next year are less that 25%.

Sperm quality, inflammation (e.g. prostatitis, orchitis), genital injuries, congenital abnormalities (e.g. hypospadias), other pathological conditions (e.g. varicocele), or exposure at work in high temperature environments, may affect sperm quality.

A quite useful genetic test given in IVF clinics is FISH (Fluorescent In Situ Hybridisation). FISH analysis is a genetic test screening for genetic abnormalities providing information about the sperm chromosomes. It consists of sperm chromosome-specific DNA probes labeled with fluorochromes. FISH is an advanced technique that can now facilitate evaluation of sperm aneuploidy. The test could be be usefull in repeated failure attempts and/or poor quality embryos.

Infertility is not primarily a woman’s problem, as it is mistakenly believed. It is estimated that infertility for about half of couples is due to a male factor, either alone or in addition to female factors. So, if a couple suffers from infertility problems men should also be evaluated for infertility.

However, the routinely used in IVF clinics semen analysis testing appears to be inadequate in diagnosing the male factor infertility. In many cases couples dealing with conception problems have given a basic semen analysis testing result that is normal in terms of sperm concentration, motility and morphology. Yet the problem remains. In such cases genetic screening tests that can detect genetic abnormalities can be of great help, comprising diagnostic tools of great clinical value.

DNA fragmentation test is a genetic test that according to fertility doctors is associated with every fertility checkpoint and in contrast to conventional semen analysis it can discriminate between the sperm of fertile and infertile men. This test could explain the reason why you are not parents yet as high levels of DNA fragmentation can inhibit a successful pregnancy despite the type of fertility treatment provided. High levels of damaged DNA have been correlated to a series of things like infections, smoking, and exposure to environmental toxic chemicals.