{{merge|Embryonic stem cells}}
'''Embryonic stem cell''' research is the utilization of [[stem cells|stem cells]] from [[embryo]]s which can then be grown in a laboratory culture and produce specialized cells to treat [[disease]]s or used for research purposes. The most common source of such cells is discarded embryos at [[fertility clinic]]s - the process of [[IVF]] typically produces two or three 'leftover' embryos for each treatment, which are usually discarded. The use of embryonic stem cells in medicine has met with some controversy, particularly from the [[pro-life]] movement that is concerned about the destruction of embryos that they believe constitute human life.<ref>http://www.washingtonpost.com/wp-dyn/content/article/2005/07/29/AR2005072900158.html</ref>