11/30/2025
Embryo biopsy - How do they do that?!
If you’re watching this, you’re seeing a blastocyst under the microscope as a tiny group of cells is gently removed for testing. And the biggest question I hear is: Does this harm the embryo?
Here’s what I tell my patients:
A blastocyst has two parts—
• Inner cell mass: the cluster of cells that becomes the fetus
• Trophectoderm: the outer layer that becomes the placenta
During a biopsy, we remove just a few trophectoderm cells. These are not cells destined to form the baby, and research shows this procedure, when performed by experienced embryologists, does not reduce success rates.
So why do people choose to biopsy an embryo?
To gather information that can guide treatment and reduce uncertainty. Testing can include:
• PGT-A: screening for chromosome differences that may impact implantation or miscarriage risk
• PGT-M: testing for a specific inherited genetic condition carried by the parents
• PGT-SR: evaluating structural chromosomal rearrangements
Biopsy isn’t right for everyone—but for some, it provides clarity, reduces the chance of a failed transfer, and helps choose the best embryo for transfer.
As always, talk with your fertility team about whether biopsy and genetic testing are right for your situation. Empowered decisions start with understanding the science.
