The invention relates to a method for making an at least double layered cell aggregate and/or an artificial blastocyst, and/or a further-developed blastoid termed blastoid, by forming a double layered cell aggregate from at least one trophoblast cell and at least one pluripotent and/or totipotent cell, and culturing said aggregate to obtain an artificial blastocyst. This artificial blastocyst has a trophectoderm-like tissue that surrounds a blastocoel and an inner cell mass-like tissue. The cell aggregate can be formed from toti- or pluripotent stem cell types, or induced pluripotent stem cell types, in combination with trophoblast stem cells. Formation of a blastoid can be achieved by culturing the cell aggregate in a medium preferably comprising one or more of a Rho/ROCK inhibitor, a Wnt pathway modulator, a PKA pathway modulator, a PKC pathway modulator, a MAPK pathway modulator, a STAT pathway modulator, an Akt pathway modulator, a Tgf pathway modulator and a Hippo pathway modulator. The invention further relates to a method for growing an at least double layered cell aggregate into an artificial blastocyst, and into a further-developed blastoid, a fetus or a live animal. The invention further pertains to an in vitro cell culture comprising the mentioned compounds and/or cell aggregates.