The technique of creating a baby from three persons uses a modified version of IVF to combine the DNA of the two parents with the healthy mitochondria of a donor woman.
The UK is set to become the first country to introduce laws to allow the creation of babies from three people. Estimates suggest 150 three-person babies could be born each year.
A further vote is required in the House of Lords. If everything goes ahead then the first such baby could be born next year.