Pre-implantation genetic diagnosis
WHAT IS PRE-IMPLANTATION GENETIC DIAGNOSIS? (PGD)
It is the genetic analysis of embryos created in vitro with the intention of transferring, to the patient’s uterus, a genetically healthy embryo: the goal being to maximise the chance of pregnancy and/or avoid the transmission of a known genetic illness.
PGD is carried out during an in vitro fertilisation cycle (IVF). Once fertilised, the eggs, now embryos are left in culture for 5 to 6 days until they reach the stage of blastocyst. At this embryonic development stage, 3 to 6 cells are removed from each good quality blastocyst. These blastocysts are then frozen in order to wait for the genetic analysis.
The cells that were removed from the embryos are sent to a specialised laboratory that performs the analysis to determine if those cells are carrying a genetic abnormality.
Healthy blastocysts are then transferred into the patient’s uterus during a frozen embryo transfer cycle.
There are two different types of PGD