Combining PGT-A with PGT-M risks trying to do too much

Area of Science:

• Reproductive Medicine
• Human Genetics
• Embryology

Background:

• Preimplantation genetic testing for monogenic disorders (PGT-M) aims to prevent serious inherited diseases.
• Combining PGT-M with preimplantation genetic testing for aneuploidy (PGT-A) may reduce miscarriage risk and transfers.
• However, combining tests risks excluding viable embryos due to inaccurate aneuploidy results.

Purpose of the Study:

• To explore the theoretical utility of combining PGT-M and PGT-A.
• To evaluate the impact of combined testing on achieving an unaffected live birth.

Main Methods:

• Theoretical analysis of the combined utility of PGT-M and PGT-A.
• Review of existing data and clinical considerations.

Main Results:

• PGT-M alone is the preferred approach for achieving an unaffected live birth.
• PGT-A offers marginal benefits in miscarriage risk reduction for PGT-M candidates (often <35 years).
• Combining PGT-M and PGT-A may lead to the exclusion of healthy embryos.

Conclusions:

• PGT-M without PGT-A is recommended for optimal outcomes in preventing monogenic disorders.
• Further experimental non-selection studies are required to assess the clinical impact of combined PGT-M and PGT-A.