In 1967, Dr. Andie Knutson surveyed public health professionals on their views on when a human’s life begins and found that they were most likely to report that life begins at conception.
In 2008, researchers surveyed patients seeking in vitro fertilization (“IVF”) procedures, members of the general public, and people working in the IVF field. While the professionals were most likely to select sperm-egg fusion (conception/fertilization), the results were mixed for patients and members of the general public.
In 2019, the most comprehensive study on when life begins received national (e.g., Daily Wire, Breitbart, Quillette, One America News Network) and international (e.g., Australia, Brazil, Russia) news coverage. In a survey of over 5,500 biologists who came from over 86 countries around the world, researchers found that 96% of academic biologists affirm the view that a human’s life begins at fertilization.
While there is a consensus of experts on biology, which is the study of life, that affirms a human’s life begins at fertilization and that a human zygote is a human, many Americans do not know when life begins. A 2018 Marist poll found that only 47% of Americans believe that life begins at conception; indeed, while 46% believe that the view “human life begins at conception” is a biological and scientific fact, 45% believe the view is a philosophical or religious belief.
 Knutson, A.L., “When does a human life begin? Viewpoints of public health professionals”, Vol. 57, NO. 12, American Journal of Public Health, Dec. 1967, https://ajph.aphapublications.org/doi/pdf/10.2105/AJPH.57.12.2163.
 Elliott T.A., Friedman, J.A., Siegel, E.T., Kort, H.I., & Nagy, Z.P. “‘When does life begin?’ Results of an online survey”, Fertility and Sterility, 2008, https://www.fertstert.org/article/S0015-0282(08)01732-9/fulltext.
 Marist Poll, “Americans’ Opinions on Abortion”, Knights of Columbus, Jan. 2018, https://www.kofc.org/un/en/resources/communications/abortion-limits-favored.pdf.
 Moore, P., “Three quarters say Longmont attack is murder“, YouGov, 2015, https://today.yougov.com/topics/politics/articles-reports/2015/04/07/three-quarters-say-longmont-attack-murder.
 Marist Poll, “Americans’ Opinions on Abortion”, Knights of Columbus, Jan. 2019, https://www.kofc.org/un/en/resources/communications/american-attitudes-abortion-knights-of-columbus-marist-poll-slides.pdf.