Genetic Testing

FAQs

• 01 What are the benefits of genetic testing?

  PGT may increase IVF conception rates by helping to identify the embryos most likely to produce a pregnancy, allowing them to be prioritised for transfer.

  Other benefits are:

  • Supporting elective single-embryo transfer to reduce multiple pregnancies
  • Reducing the incidence of miscarriage
  • Reducing the risk of a live-born child with a chromosomal abnormality
  • Reducing the number of IVF cycles necessary to achieve a successful outcome.

• 02 What are the risks?

  It’s important to keep in mind that adverse results may arise when attempting genetic testing. The chances of these occurring are usually minimal but risks are associated with:

  • Embryo biopsy: The risk of damaging an embryo during removal of cells is less than 1%. However, if an embryo is damaged, it may not be suitable for transfer into the uterus.
  • The preparation of biopsied cells: After biopsy, the removed cells are placed in a small test tube and their DNA is amplified (replicated). The cells are no longer viable in any way after this process and can only be used for the tests. Some biopsied cells (less than 2% per cycle) may not yield a test result, or the cells may be lost during transfer to the test tube. Embryos without a result from the analysis may still be transferred, but the advantages of PGT will not apply.
  • Misdiagnosis: PGT is not 100% accurate and prenatal diagnosis is still recommended following conformation of pregnancy. However, the risk of a clinical misdiagnosis resulting in a fetus or baby with chromosomal abnormalities after PGT-A is less than 2%. This is still lower than the risk of having a fetus or baby with chromosomal abnormalities without PGT. Due to the chance of misdiagnosis, as well as the presence of types of abnormalities that are not tested for (such as), your doctor will strongly recommend a non-invasive prenatal test (NIPT), ultrasound scan, Chorionic Villus Sampling (CVS) or an amniocentesis. He or she will advise this at the confirmation of a pregnancy, through an ultrasound scan, about five weeks after IVF treatment. The recommended NIPT and other tests can identify pregnancies affected by conditions such as Down syndrome. CVS would be performed at 10-12 weeks and amniocentesis at 15-20 weeks.
    Benefits of NIPT, ultrasound scan, CVS or amniocentesis: confirmation of results of genetic testing and peace of mind. Potential risks include miscarriage and bleeding.
  • No normal embryos: The test may find that none of the embryos are normal, in which case there will be no transfer procedure. The likelihood of this happening depends mainly on the patient’s age and the number of eggs retrieved. For women aged over 40, about 10-15% of cycles result in all the embryos being abnormal, which means there is no transfer. For younger patients, the risk of all embryos being abnormal is lower, sometimes significantly, as age is the most important factor affecting a woman’s prospects of falling pregnant. However, the quality of the male partner’s sperm also has to be taken into account.
  • No diagnosis or partial diagnosis: Some embryos will have no diagnosis due to the loss of the biopsied cells, or naturally poor DNA quality (often found in damaged or dying cells). Cells can regress as the embryo divides to form a blastocyst. Embryos without a result can still be transferred, at your own discretion, but the benefits of PGT will not apply in such cases. In this situation, your pregnancy will need to be carefully monitored with ultrasound examination to check the fetus’s development.

• 03 What are the alternatives to genetic testing?

  The alternative to PGT is to undergo an IVF cycle with no genetic testing of the embryos. In this case, standard prenatal testing (CVS, amniocentesis, NIPT and ultrasound examination) for abnormalities would be carried out if a pregnancy resulted from fertility treatment. These methods will identify pregnancies affected by chromosomal disorders such as Down syndrome, but do not increase the chances of a successful IVF cycle.

• 04 How much does IVF treatment cost in Australia?

  Both fresh and frozen embryo transfers can be effective.

  Fresh transfers occur in the same cycle as egg collection, while frozen transfers take place later after embryos are frozen and thawed. Your fertility specialist will guide you on the approach that best suits your health and treatment goals.