Fertility doctors in Greece and Spain say they have produced a baby from three people in order to overcome a woman’s infertility.
The baby boy was born weighing 2.9kg (6lbs) on Tuesday. The mother and child are said to be in good health.
The doctors say they are “making medical history” which could help infertile couples around the world.
But some experts in the UK say the procedure raises ethical questions and should not have taken place.
The experimental form of IVF uses an egg from the mother, sperm from the father, and another egg from a donor woman.
It was developed to help families affected by deadly mitochondrial diseases which are passed down from mother to baby.
It has been tried in only one such case – a family from Jordan – and that provoked much controversy.
But some fertility doctors believe the technology could increase the odds of IVF too.
This is all about mitochondria – they are the tiny compartments inside nearly every cell of the body that convert food into useable energy.
They are defective in mitochondrial diseases so combining the mother’s DNA with a donor’s mitochondria could prevent disease.
But there is also speculation mitochondria may have a role in a successful pregnancy too. That claim has not been tested.
The patient was a 32-year-old woman in Greece who had endured four unsuccessful cycles of IVF.
She is now a mother, but her son has a tiny amount of his genetic makeup from the donor woman as mitochondria have their own DNA.