Researchers have turned male skin cells into female egg cells that produced live offspring. 

In a stunning breakthrough, international researchers have bred baby mice using implanted egg cells that were once cells taken from male mice. 

The researchers took skin cells from the tail of mature male mice and turned them into stem cells - which are cells that can develop into a range of other cell types. 

By growing these stem cells in the lab, some cells begin to lose their Y chromosome, and duplicate their remaining X chromosome, meaning they slowly changed from having 'male' XY chromosomes to 'female' to XX chromosomes.  

The researchers then got these stem cells to grow into egg cells. 

When fertilised and planted into a mouse uterus, about 1 per cent of the embryos produced babies (7 out of 630). 

The researchers say this could help push fertility research forward, though there will need to be much more research into the impact of using this method to reproduce.

The full report is accessible here.