What are the main aims of preimplantation genetic testing (PGT) in IVF?

• A. To screen embryos for aneuploidy, monogenic disorders, and structural rearrangements.
• B. To increase the number of embryos produced.
• C. To replace standard genetic counseling.
• D. To detect infectious diseases.

Answer: (A)

The main aim of preimplantation genetic testing in IVF is to assess the genetic status of embryos before transfer so that the healthiest embryos are selected for implantation. This helps improve the chances of a successful pregnancy and reduce the risk of genetic problems in the baby.

In practice, this testing covers three areas. First, screening for aneuploidy (an abnormal number of chromosomes) which is a common cause of implantation failure, miscarriage, and congenital issues, especially with advancing maternal age. Second, testing for known single-gene disorders in families (monogenic disorders) so that embryos carrying the disease-causing mutation can be avoided. Third, checking for structural chromosomal rearrangements (such as translocations) that can lead to unbalanced embryos and pregnancy loss.

The other statements aren’t accurate because PGT is not about increasing the number of embryos produced, it does not replace genetic counseling (which remains important for interpreting risks and options), and it does not detect infectious diseases.