The remarkable feat was to create synthetic human embryos from stem cells in the laboratory.
Scientists hope that these embryos, which completely eliminate the need for an egg or sperm, will provide a unique opportunity to study and develop treatments for various genetic diseases.
That said, this work will likely raise a number of ethical questions, especially since the creation of synthetic human embryos is against current legislation in a number of countries.
It would certainly be illegal to implant them in a real uterus and it is unclear how far they could grow under these circumstances.