Can you explain what PGS is?

Pre-implantation Genetic Screening or PGS, is an assisted reproductive treatment where we undertake the genetic analysis of the embryo and replace a genetically normal embryo back into the womb.

This is also commonly referred to as comprehensive chromosomes screening or CCS. As part of the treatment, the patients have to go to an IVF treatment process which will involve taking the fertility drugs, going to the egg collection, and once the eggs have been collected and inseminated, the embryos will become cultured up to blastocyst or day-five stage.

After blastocyst stage, we will then take a few cells from the embryo and these cells will then be subjected to the genetic analysis using the next generation sequencing platform. We will then assess which of these embryos are genetically normal. After the genetic analysis has been performed, we will then start another cycle for yourself and this genetically normal embryo – one or two – would be replaced back into the womb in a frozen embryo replacement cycle.

This intervention is of more relevance to patients, for example, women trying for pregnancy may be over 38 or 40 way there is a higher incidence of the genetic errors in the embryo leading to the reduction the fertility rates and a higher incidence of genetic problems in babies such a Down’s Syndrome. This can also be of relevance to patients with repeated treatment failures because repeated treatment failures can either be related to the failure of the implantation or to the embryo health.

Assessing the embryo health is only one aspect that we understand as of now and is a little bit more about the genetics. So by testing the embryos for genetic normality, we are trying to correct one of the potential factors that might be contributing to the treatment failures or preimplantation failures.

The other group of patients would be repeated miscarriages. if patients have multiple miscarriages which have been less than 12 weeks of gestation, sixty percent of these miscarriages could be genetic in nature. So by doing PGS and replacing a genetically normal embryo back, we are hoping to correct the problem leading to an ongoing pregnancy and childbirth.

We also offer pre-implantation genetic diagnosis. Pre-implantation genetic diagnosis is of relevance to the patients with single gene disorders or maybe double gene disorders. Largely it is for single gene disorders. Generally, for these cases, NHS funding for the treatment should be available, and if you would want to explore those then it would require an initial assessment of the genetic condition, involvement of a clinical geneticist, and then planning your treatment. These are some of the other genetic services that we offer at the clinic.

By | 2017-07-06T16:56:43+00:00 December 15th, 2016|Genetic Testing|Comments Off on Can you explain what PGS is?

About the Author:

Ms Shipra Krishna is an extensively experienced Consultant Gynaecologist and specialist in Reproductive Medicine. She worked as a Consultant Gynaecologist and Specialist in Reproductive Medicine at CARE Fertility and Centre for Reproductive and Genetic Health (CRGH) since 2011. She is Medical Director of London IVF and Genetics Centre.