Preimplantation Genetic Screening
Preimplantation Genetic Screening (PGS) is a state of the art laboratory technique in which the embryo is tested for certain chromosome abnormalities prior to being transferred into the uterus. The aim is to increase the likelihood that a healthy embryo will implant to reduce the possibility of an early miscarriage. PGS would also be expected to reduce the incidence of fetal abnormality and birth defects related to chromosomal disorders.
Preimplantation genetic screening is therefore a way of diagnosing whether an embryo is apparently normal or abnormal before transferring the embryo into your uterus. This is a complex test which involves embryo biopsy (removing a single cell from the embryos) and analyzing the chromosomes of the cell removed from the embryo using a staining technique called FISH.
Preimplantation geneteic screening is performed for four reasons
Advanced maternal age (women over the age of 35 years)
Previous unsuccessful IVF despite apparently good quality embryos
Recurrent miscarriages- many miscarriages are due to abnormal embryos
Previous abnormal baby or previous pregnancy terminated due to fetal abnormality
Each embryo is tested for 9 chromosomes. This is more than what other units would test (who test between 5 and 7 chromosomes). Three of our embryologists are licensed by the HFEA to perform embryo biopsy whereas only very few embryologists in the country have these skills.