
PREIMPLANTATION GENETIC DIAGNOSIS
PGD is an embryo diagnosis to detect genetic diseases. It is an examination of the abnormalities of the embryo at the gene level and is used to diagnose genetic disorders to avoid inherited diseases in the event that the father or mother knows that they are the family carriers of conditions like Thalassemia.
Benefits of PGD
Undergoing PGD treatment in Thailand can help prevent genetic diseases that occur in infants. It reduces the need to terminate pregnancy and reduces the likelihood of birth defects that have to be cared for throughout life which, of course, will affect the parents. Genetic diseases cannot be cured, but we can alleviate the symptoms in many of the diseases.
Any couple can request PGD in their IVF cycles at our clinic in Bangkok. However, couples benefitting the most are those who are at increased risk for chromosomal abnormalities or specific genetic disorders due to indications in their family medical histories. This includes women who had a previous pregnancy with a chromosomal abnormality, or who have had a number of miscarriages. Men with some types of sperm abnormalities may also create embryos with higher rates of chromosomal abnormalities.
Where there is a 25-50% chance of having a child affected by a specific genetic disease, PGD can be used to differentiate the embryos that are affected from those unaffected. It can also be used to identify carrier embryos when applicable. Using PGD, the unaffected embryos can be easily identified and safely transferred to the uterus to attempt a pregnancy.
How is PGD Performed?
PGD is performed by removing the embryonic cells and analyzing the embryonic genes. Embryonic cell extraction can be done in two stages: when the embryo is 3 days old and when the embryo is 5 days old. If the embryos are found to be viable, then they will be returned to the uterus of the mother to attempt a healthy pregnancy.
PGD for Gender Selection in Thailand
Couples undergoing PGD can reliably choose the gender of their baby at the VFC Center at Vejthani Hospital. Choosing the sex of a baby was based on unreliable techniques in the past that were successful only about 50% of the time. PGD has become the only method that delivers the gender of choice with almost 100% accuracy.
The sex of a baby is determined during conception by the chromosomes of the egg and sperm. People have two gender chromosomes, ‘X’ and ‘Y’. Female eggs contain only the X chromosomes. Male sperm contains either an X or Y chromosome.
An embryo will be female if conception results in an XX embryo, and male if it results in an XY embryo. PGD can determine which embryos are XX and XY by using a technology called Fluorescent In-Situ Hybridization (FISH). Two probes are used which emit fluorescent light of different colors. The X and Y chromosomes respond to the two lights and appear as different colors as well.
If you feel you’re a candidate for PGD for either genetic disease or gender selection reasons, make an appointment at the VFC Center at Vejthani Hospital.