Common embryo testing procedures require months of laboratory work, but the latest tool, known as karyomapping, can be completed within two weeks, meaning a couple can undergo tests without breaking from their IVF treatment cycle.

To perform the karyomapping, doctors first obtain DNA from cheek swabs of the parents and a family member affected by the disorder.

"In more than two decades of working this field, this is the single biggest technological leap I have seen. Karyomapping is already making a significant difference to patients," said Dagan Wells at Reprogenetics UK, an Oxford-based company that tested the embryos.