Preimplantation Genetic Diagnosis, also referred to as PGD testing, is the process that doctors follow to check your embryos for genetic defects, prior to implanting them in your uterus.
It raises the chances of IVF success by allowing the doctor to select the best of embryos for implantation.
PGD is especially helpful in patients who have chromosomal or genetic disorders and fear passing them on to their children.
Although there have been some concerns regarding the use of this technology, the benefit of the procedure has caused its popularity and use to grow significantly.
What is the difference between PGD and PGS?
Preimplantation genetic screening (PGS) does not check the DNA or identify a specific genetic disease but uses PGD techniques to simply identify the embryos at risk.
Using PGS, embryos are screened for aneuploidy (abnormal numbers of chromosomes), which is the main cause of miscarriage and implantation failure, causing a lot of frustration to IVF patients.
Besides, disorders like Down’s syndrome can be avoided with PGS screening.
Using PGS, the doctor can simply identify the embryos that have chromosomal anomalies, so those can be left behind and only the normal ones are transferred, thus raising the possibility of successful pregnancy.
How is PGD performed?
First, the normal process of in vitro fertilization will be carried out in which the egg and sperm are fertilized in the lab. The resultant embryo will divide into multiple cells in the next three to five days.
PGD-IVF process will be performed over that embryo in the following steps:
- Biopsy: One cell is removed at day three and several cells are removed at day five (blastocyst stage) of the embryo. The day-5 biopsy on blastocyst is considered by many experts to be the gold standard for PGs and PGD testing.
- DNA evaluation: While the embryo is frozen in the lab, the DNA of extracted cells is evaluated to check for presence of any problematic gene.
- Embryo Selection: The embryos that pass as problem-free will be transferred to the uterus and if there are still other good ones left, they will be frozen for future use.
How much time is required for PGD?
If you opt for PGD testing with IVF, you will have to wait 7-10 days extra to allow for the screening of embryos before implantation.
Do you need PGD with IVF?
PGD is advised if you can identify with any of the following five conditions:
- You are seeking IVF in advanced age – after 36 years of age, there is a greater chance of chromosomal anomalies in female eggs and a lot of people opt for PGD
- You have family history of genetic diseases
- You have had recurrent miscarriages
- You or your partner is a carrier of chromosomal translocations
- You have suffered repeated IVF failure
With PGD your doctor can identify translocations in chromosomes (rearrangements of parts of chromosomes) as well as single mutations in genes that can cause genetic diseases.
According to Advanced fertility, the below chart explains the risk of chromosomal abnormalities by growing female age:
Problems like fragile X, myotonic dystrophy, thalassemia, cystic fibrosis and about 4,000-single gene disorders can be detected with the help of PGD.
The most common reason to seek PGS with IVF is advanced age. Women seeking IVF in late 30s or in their 40s have grater chances of chromosomal anomalies in their eggs, and PGS helps check for atypical embryos.
Cost of PGD and PGS
IVF with PGD in India – starts from $5,000
IVF with PGD in Thailand – starts from $12,500
For your custom quote for IVF with PGD testing and the current specials at our associate clinics, please get in touch via the form on the right
Advantages of PGD
- With the help of PGD testing, over a hundred different genetic diseases can be detected
- It allows you to see of potential problems in the embryo to let you decide if you want to continue with the pregnancy
- By detecting aneuploidy, PGD shows the probability of miscarriage and implantation failure – thus allowing for greater IVF success
- It also allowed for sex detection to help couples balance their families but since people started abusing it and the government declared sex detection illegal, doctors in India and Thailand stopped offering it.
Please do not contact for sex detection of your baby. It is illegal.
Risks of PGD Testing
- Some people believe that biopsy so early on could disturb the embryo
- Extra time needed before embryo implantation
- If the results are not recorded carefully, an embryo with a chromosomal defect could be transferred to the uterus and healthy embryos are discarded
- Not all genetic diseases can be detected – like the ones that begin to show only when the carrier reaches middle age. PGD/PGS greatly improves the chances of conceiving a child without a genetic disorder but it does not completely eliminate the risk.
Alternatives to PGD/PGS
Preimplantation genetic testing is done on embryos in the IVF procedure but AFTER the pregnancy is confirmed, there are some tests that can be done for genetic abnormalities:
- Chorionic villus sampling (CVS) – biopsy of the placenta at 10 -12 weeks of pregnancy to detect for fetal genetic abnormalities. If detected, you may have to consider an abortion.
- Amniocentesis – performed 16 to 18 of pregnancy. In this test the amniotic fluid is checked for genetic abnormality in the fetus.
- Ultrasound & blood tests – additionally help in checking for some abnormalities. If suspected, advanced tests may be recommended to confirm the diagnosis.
- Donor gametes – IVF with donor eggs or donor sperm may be considered if there is a high risk of transferring genetic problems to the baby.
For more information on IVF with PGD or PGS and to know about the price of PGD testing in India and Thailand, get in touch via the form on the right