The groundbreaking development is not intended to create babies outside of the womb.
Instead, the aim is to one day produce replacement organs for humans.
Experts made fake embryos – which are created without fertilised eggs – using stem cells from mice.
After little over a week, these embryo-like structures self-assembled with a rudimentary beating heart, blood circulation, the early stages a brain and intestinal tracts.
They were grown in an artificial womb but stopped developing after eight days.
“The embryo is the best organ-making machine and the best 3D bioprinter,” said project leader Professor Jacob Hanna, from the Weizmann Institute in Israel.
“We tried to emulate what it does.”
The synthetic embryos were not exactly the same as a natural mouse’s, but organs did give every indication of being functional.
For now, scientists believe the breakthrough will help them to better understand how organs and body tissues form at the early stages of life as we know it.
“Our next challenge is to understand how stem cells know what to do – how they self-assemble into organs and find their way to their assigned spots inside an embryo,” he continued.
“And because our system, unlike a womb, is transparent, it may prove useful for modeling birth and implantation defects of human embryos.”
