Scientists have created a model of an early human embryo from skin cells, a discovery which they say will revolutionise research into the causes of early miscarriage, infertility and early human development. Researchers have successfully reprogrammed these fibroblasts or skin cells into a 3D cellular structure that is similar to human blastocysts. Called iBlastoids, these can be used to model the biology of early human embryos in the laboratory, according to a new study. Scientists say this is a significant breakthrough for the future study of early human development and infertility. A few days after an egg has been fertilised, it develops into a blastocyst.