The researchers say creating embryo-like structures in the lab will help scientists understand why pregnancies fail at an early stage. Picture: Pixabay

London - Scientists have come another step closer to making human embryos in the laboratory.

Researchers at Cambridge University used stem cells from mice to create an artificial embryo-like structure.

The breakthrough suggests embryos could eventually be grown from stem cells – "blank" cells that can grow into any tissue – without the need for sperm or eggs.

The Cambridge team first created a simple structure resembling a mouse embryo last year, using two types of stem cells and a "scaffold" on which to grow.

But their latest research goes much further by creating embryo-like structures with three types of stem cell that would eventually form a baby’s body, a placenta and a yolk sac.

This three-part division, called gastrulation, is vital to allow an embryo to become a baby with all its tissues and organs in the right place.

Professor Magdalena Zernicka- Goetz, the biologist who led the research, said: "Our artificial embryos underwent the most important event in life in the culture dish. They are extremely close to real embryos.

"To develop further, they would have to implant into the body of the mother or an artificial placenta." 

Dr Christophe Galichet, a senior laboratory research scientist at the Francis Crick Institute who was not involved in the research, said: "Understanding human early embryo development is not as trivial as with the mouse. Indeed, work on early human embryos is highly and tightly regulated."

But he added: "While the paper did not use human stem cells, it is not too far fetched to think the technique could one day be applied to studying early human embryos, though this has not been done yet."

It would be a substantial next step from IVF, which allows infertile couples to have a baby without having sex by fertilising the egg with sperm in the laboratory.

If successful in humans, the technique being developed could remove the need for sperm or egg cells altogether.

The researchers say creating embryo-like structures in the lab will help scientists understand why pregnancies fail at an early stage.