Preimplantation Genetic Testing (PGT)

Causes & Risk Factors

PGT is considered in specific IVF scenarios rather than being routine for every IVF cycle:

•  Advanced maternal age — increases the likelihood of chromosomal abnormalities in embryos, making PGT-A potentially informative.

•  Recurrent IVF implantation failure — may prompt consideration of PGT-A to assess embryo chromosomal status.

•  Recurrent pregnancy loss in the context of IVF — chromosomal abnormality is a common contributor.

•  Known carrier status for a specific genetic condition in one or both partners — the primary indication for PGT-M.

•  Known parental chromosomal rearrangement — relevant to both PGT-A and structural rearrangement testing (PGT-SR).

Symptoms & When to Test

PGT is not symptom-driven — it is a proactive genetic screening step integrated into a planned IVF cycle, decided in advance with the fertility team.

•  PGT-A — considered in selected IVF patients based on individual clinical circumstances such as age or prior IVF outcomes

•  PGT-M — considered when one or both partners are known carriers of a specific genetic condition with significant risk of transmission

When Should You Consider Testing?

The decision to pursue PGT is made before or during IVF cycle planning, in discussion with your fertility specialist and, for PGT-M, a genetic counsellor — not in response to a specific symptom.

Why Tests Are Combined

PGT-A and PGT-M serve fundamentally different purposes and are not interchangeable: PGT-A broadly screens for chromosome-number abnormalities across all embryos, while PGT-M is custom-designed around one specific known familial genetic variant — a couple may need one, the other, or occasionally both, depending on their situation.

For PGT-M specifically, appropriate genetic counselling and test design work must be completed before the IVF cycle begins, since the testing approach has to be built around the exact variant identified in prior carrier or diagnostic testing.

It is important to understand that PGT is a genetic screening approach for embryos and does not guarantee implantation, pregnancy, or a healthy baby — it reduces, but does not eliminate, the risk of transferring an embryo with the specific abnormality being tested for.

Tests Available at NPL

Most reproductive hormone and genetic tests do not require fasting. However, some tests have specific timing requirements (such as a particular day of the menstrual cycle), and if other tests are ordered at the same time, fasting may be required for those investigations. Please follow the preparation and timing instructions provided by your doctor or NPL.

Home Sample Collection

PGT does not involve a home sample collection service. The embryo biopsy is performed at the IVF/fertility clinic by the embryology team, as part of the IVF procedure itself.

Once the embryo biopsy is completed, the biopsied cells are securely transported to NPL's NABL ACCREDITED UNDER ISO 15189:2022 laboratory for genetic analysis (PGT-A or PGT-M as applicable).

Results are delivered securely to your fertility specialist and IVF team, who will discuss the findings with you as part of your embryo transfer planning.

For questions about the IVF or embryo biopsy process itself, please coordinate with your fertility clinic; NPL can assist with queries related to the genetic analysis and reporting timeline at +977 1 5970147.

When to See a Doctor

•  Before starting an IVF cycle, if advanced maternal age or prior IVF failure is a concern

•  If you or your partner have a known genetic condition or are a known carrier

•  After recurrent pregnancy loss in the context of IVF treatment

•  For genetic counselling before designing a PGT-M test