The Human Developmental Cell Atlas procures human embryonic and fetal samples acquired through the already established collaboration with Karolinska Institutet and the gynecology Clinics at Karolinska University Hospital and Danderyd Hospital, and process them according to the highest ethical standards. Tissue is only retrieved from clinical routine abortions, through a process in which no scientists are involved. Unquestionable written consent after oral and written information is always required. All procedures have been approved by the Ethical Review Board, and the Swedish Board of Health and Welfare (”Socialstyrelsen”). Rigorous care is taken to ensure the patients’ anonymity when tissue is handled during the analytical processes, which include single cell RNA sequencing and spatial analyses, computational analysis to define cell types, model their activity, build the 3D atlas, and store and disseminate data. We ensure that all ethical, experimental and computational procedures are aligned and integrated with the international Human Cell Atlas.