Genetic testing of embryos (PGT)

PGT · PGD · preimplantation genetic testing · embryo testing in IVF · embryo screening

During IVF, a few cells are taken from an embryo, and their genes or chromosomes are checked. An embryo with no problems found is placed in the uterus.

When a genetic condition runs in the family, after repeated failed IVF or miscarriages, and sometimes when the mother is older.

⏱ Duration: it is part of an IVF cycle; testing the embryos usually takes from a few days to a few weeks

Be sure to tell your doctor

What genetic conditions run in the family. Bring the genetic reports
How many pregnancies, miscarriages, and IVF attempts you have had
All your medicines and health conditions
What you expect from the test. The doctor will explain what it can and cannot do

How to prepare

Geneticist. Before IVF, a geneticist will talk with you. For a single-gene test, the test is set up ahead of time, sometimes over several weeks.
Tests for the couple. Often both partners, and sometimes relatives, give blood. It is used to set up the test.
IVF cycle. Follow your doctor's plan for stimulation, egg retrieval, and shots. Do not change it on your own.

What to bring

Your family's genetic reports
ID for both partners
Results of past IVF cycles

How it goes

You go through a normal IVF cycle: stimulation and egg retrieval
The embryos grow in the lab, usually for 5 to 6 days
An embryologist takes a few cells from the outer layer of the embryo
The embryos are usually frozen while the testing is done
The cells are checked in a genetics lab
The doctor goes over the result with you and chooses an embryo to transfer

What you'll feel

You do not feel the embryo testing itself. It is done in the lab
You feel the same as in a normal IVF cycle: shots, egg retrieval, sometimes a pulling feeling in the belly

Afterwards

The embryo transfer is usually in one of the next cycles
The test lowers the risk but is not a full guarantee. During pregnancy, the doctor may offer its own checks
Sometimes there are no suitable embryos. The doctor will talk about the next plan

Contact a doctor straight away if

After egg retrieval: severe belly pain or bloating, shortness of breath, or little urine: see a doctor right away
Heavy bleeding or fainting: call emergency services

Common questions

Does the biopsy harm the embryo?

The cells are taken from the layer that later becomes the placenta. The risk to the embryo is considered small. The embryologist can tell you more.

Can I choose the baby's sex?

Without a medical reason, choosing the sex is usually not allowed. The test is used to avoid illness.