Preimplantation Diagnostics (PID / PGT)

The Preimplantation Diagnostics (PID), also known as Preimplantation Genetic Testing (PGT), enables the genetic testing of embryos as part of an IVF or ICSI treatment before an embryo is transferred to the uterus.

With preimplantation diagnostics, embryos can be examined for chromosomal changes or specific genetically determined diseases, depending on the indication. The aim is to obtain additional genetic information for the selection of an embryo for transfer.

How does preimplantation diagnostics work?

Genetic testing is usually performed on embryos that have developed to the blastocyst stage (Day 5 or 6) after fertilization.

A few cells are taken from the trophectoderm, the outer cell layer of the blastocyst. This tissue later primarily develops into the placenta. The removed cells are then examined in a specialized genetic laboratory.

Since genetic analysis takes some time, embryos are usually frozen by vitrification after biopsy. Once the genetic result is available, a joint decision can be made as to which embryo is suitable for a later embryo transfer.

PGT-A – Testing for chromosomal changes

PGT-A (Preimplantation Genetic Testing for Aneuploidies) examines embryos for deviations in chromosome number. Embryos with a normal number of chromosomes are referred to as euploid.

Chromosomal changes occur more frequently with increasing maternal age and are an important reason why embryos do not implant or a pregnancy ends prematurely.

PGT-A can identify embryos with an unremarkable chromosomal finding for transfer. This can significantly increase the probability of success per embryo transfer and reduce the risk of miscarriage.

PGT-A can be particularly useful for certain patients with advanced maternal age, recurrent miscarriages, or recurrent implantation failure.

PGT-M – Preimplantation diagnostics for monogenic hereditary diseases

PGT-M (Preimplantation Genetic Testing for Monogenic Disorders) is used when a known monogenic disease is present in a family. These are diseases caused by a change in a single gene.

As part of an IVF or ICSI treatment, the resulting embryos can be specifically examined for the known familial genetic change. This allows embryos to be identified that are not affected by the genetic disease under investigation.

PGT-M can offer couples with an increased risk of passing on a serious hereditary disease the opportunity to significantly reduce this risk for their future child.

Preimplantation Diagnostics in Switzerland

The performance of preimplantation diagnostics in Switzerland is regulated by law and subject to certain conditions. Whether PGT-A or PGT-M is advisable and possible in an individual case is assessed during a detailed fertility medicine and – depending on the indication – genetic consultation.

At the Kopelli Fertility Clinic, we provide individual advice on the possibilities of preimplantation diagnostics and jointly clarify which diagnostic and therapeutic steps are appropriate for your personal situation.