ASRM Ethics Committee Chair Co-Authors Science Article - Argues to Revisit the “14-Day Limit” on Human Embryo Research

Sigal Klipstein, MD, Chair of the ASRM Ethics Committee, co-authored an article appearing in the most recent issue of Science. The article entitled, “Human embryo research beyond the primitive streak,” explores the question of whether it is time to rethink the historical prohibition, now 40 years old, of culturing human embryos for research beyond 14 days consecutive or growth, or beyond the development of the primitive streak.

Klipstein and her international team (representing the Netherlands, the United Kingdom, China, and the United States) of co-authors, Insoo Hyun, Annelien L. Bredenoord, James Briscoe and Tao Tan, offer an important framework to use in evaluating the potential merits of extending the time period during which human embryo research is acceptable. The article traces the history of the 14-day rule back to policy processes in the US and UK in the late 70s and early 80s, which were developed following the first successful birth from In Vitro Fertilization in 1978. The authors point out that in the 40 years since the introduction of the 14-day rule, embryology has advanced to the point where research that was once hypothetical may very well be possible, forcing a reexamination of the 14-day rule. The authors explore 5 categories of scientific goals which could be advanced, including attempting to understand why 3% of births show some form of congenital abnormality, and why many pregnancies miscarry.

Furthering research in these areas aims to improve human fertility and understand the earliest underpinnings of disease, knowledge whose ultimate goals include improving pregnancy outcomes and human health. They also propose 6 principles which should inform any discussion of moving forward: strong scientific justification, well defined increments, independent peer review, public dialogue, informed consent, and separation of clinical care from research.

To quote from the article:

“It is likely possible to culture human research embryos past the 2-week limit and [research] suggests that doing so will yield scientific insights that could prove important for human health and fertility. We thus urge policy-makers, and the International Society for Stem Cell Research (ISSCR), which will soon release updated guidelines for stem cell and embryo research, to consider a cautious, stepwise approach to scientific exploration beyond the 14-day limit.”

Read the collaborative position statement, Ethics in embryo research: a position statement by the ASRM Ethics in Embryo Research Task Force and the ASRM Ethics Committee, addressing ethical considerations in embryo research.

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