Beginning of pregnancy controversy

Controversy over the beginning of pregnancy occurs in different contexts, particularly being discussed within the abortion debate in the United States according to groups such as the Guttmacher Institute. Depending on when pregnancy is considered to begin, some methods of birth control as well as some methods of infertility treatment might be considered to work as an abortifacient. The controversy is not primarily a scientific issue since knowledge of human reproduction and development has become very refined; linguistic questions remain debated for other reasons. The issue poses larger social, legal, medical, and political ramifications should one equate the 'beginning of pregnancy' with the 'beginning of an individual human being's life', a position that has been taken by groups such as Concerned Women for America.

A major complication is that ideological and religious concepts such as "ensoulment" (whether or not a human being is said to have gone from mere matter to having a spiritual entity inside) and "personhood" (whether or not a human being is said to be a distinct individual with innate human rights versus otherwise) exist outside of scientific analysis, and thus many individuals have argued that the beginning of pregnancy cannot be determined strictly through physical evidence alone. No experiment exists (or can exist) to measure the spirituality of an object or living thing the way that height, temperature, weight, etc. can be studied. Generally speaking, ideological and religious commentaries have argued that pregnancy should be stated as beginning at the first, exact moment of conception in which a human sperm makes full contact with an egg cell (this is easily visualized by picturing the outside of the egg as a single sperm hits it), many of these arguments being related to the anti-abortion movement. That doctrine has not found acceptance scientifically.

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