Preimplantation genetic testing - Medical Specialty | Hirslanden Switzerland

Preimplantation genetic testing for aneuploidy (PGT-A) is a highly developed procedure for older couples who would like to become parents or if in vitro fertilisation becomes particularly difficult. In Switzerland, the treatment is successfully provided by specialist doctors at the Hirslanden Private Hospital Group.

PGT-A and PGT-M diagnostic methods

Medicine is now so advanced that it can investigate the genetic material of embryos even before implantation. PGT-M (preimplantation genetic testing for monogenic disease) is used as a PID (preimplantation diagnosis) method for couples with hereditary diseases such as cystic fibrosis. PGT-A is then indicated if all embryos need to be investigated for chromosomal abnormalities.

Patients suitable for PGT-A
  • Women aged over 38
  • After miscarriages
  • After several unsuccessful embryo transfers
  • If the partner’s sperm count is too low
  • If couples want to ensure that no embryos with abnormal chromosome numbers are implanted
PGT-A procedure

On the fifth or sixth day, the embryo develops into the so-called blastocyst. For the embryo biopsy, geneticists only take five to ten of a total 300 cells. 

These tiny tissue samples are carefully labelled and taken by courier to the special genetics laboratory Igenomix in Spain. It takes around ten days to get the results.

If several blastocysts are available, the likelihood of having an embryo suitable for implantation is over 90%. In 98% of cases, PGT-A identifies embryos that would be unviable or lead to miscarriage. 

Successful methods

Unlike other techniques, the embryo transfer does not take place immediately with preimplantation genetic testing for aneuploidy (PGT-A). If all the data is available and no chromosomal abnormalities have been established, the specialist doctors at the Hirslanden clinic insert the embryos four weeks after egg collection. The success rate of PGT-A is around 60% – regardless of the age of the woman.