National human embryo and embryoid research policies: a survey of 22 top research-intensive countries.

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.

Global update: USA.

Despite the political nature of stem cell research, this area of science continues to flourish in the USA. In 2011, the NIH funded approximately US$1.2 billion in stem cell research - a steady increase from past years - with US$123 million devoted to human embryonic stem cells.