Embryo culture

After fertilization is confirmed, embryos are cultured in incubators. Embryologists in the lab carefully control factors such as nutrients, humidity, temperature, and exposure to light.

During this time, some embryos will stop developing, but the ones that continue to develop will reach the blastocyst stage by culture day five or six. Approximately 25 to 50 percent of fertilized eggs will become blastocysts and will be of high-enough quality for transfer to the uterus or cryopreserve.

Preimplantation genetic diagnosis (PGD) and preimplantation genetic screening (PGS)

PGD involves the removal of a single cell from an embryo and testing the cell for certain inherited diseases, such as cystic fibrosis and muscular dystrophy.

PGS may be used to detect if the embryo has a chromosome abnormality.

This diagnosis can be made before embryos are transferred into the uterus for the establishment of a pregnancy. This service is available for couples at risk for passing on a genetic disease to their children and those who have a high risk of having a child affected by a chromosomal disorder. Additional information will be provided at your preliminary visit.

Last reviewed: 
February 2018

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