Research using human embryos and embryoids has expanded in recent years due to technological advances. Surveying laws and guidelines among the top research and development (R&D) investing nations highlights existing barriers to expanding this area of research. Of the 22 nations surveyed, we found 12 countries with a 14-day limit, one with a seven-day limit, five with prohibitions and four without national laws or guidelines that limit or prohibit human embryo research. Sixteen national laws or guidelines define an embryo or related entities, with five nations limiting human embryoid research. Other laws are ambiguous in relation to embryoid research, leave unanswered questions regarding what research is permitted or restricted and need additional clarity for researchers.

Recent technological advances have helped scientists understand early human development. However, scientists’ ability to fully explore their potential comes in conflict with national and state-level policies in the USA. In 2016, for the first time, researchers were able to grow human embryos in culture up to 14 days but stopped because of scientific and legal limits. Other researchers have used stem cells in culture to create organized models of early human development, known as embryoids or cell-based embryo models. In this paper, we review federal and state laws that affect US human embryo and embryoid research. While federal policies focus on funding, state laws are often associated with human embryonic stem cells, abortion, fetal tissue research, and reproductive cloning. Of the 29 states with laws impacting human embryo research, only 11 states ban it, and none address embryoids directly, although five states limit aspects of this research. Overall, this complicated landscape suggests that additional national guidance would help scientists and the public navigate these controversial areas of research, however, it is unlikely to happen, considering the lack of past progress determining embryo research policy.