Viability and Established Pregnancy
A related issue that comes up in this debate is how often fertilization leads to an established, viable pregnancy. Current research suggests that fertilized embryos naturally fail to implant some 30% to 70% of the time. Of those that do implant, about 25% suffer early pregnancy loss by the sixth week LMP (after the woman's Last Menstrual Period), and an additional 7% miscarry or are stillborn. As a result, even without the use of birth control, between 50% and 70% of zygotes never result in established pregnancies, much less birth.
Read more about this topic: Beginning Of Pregnancy Controversy
Famous quotes containing the words established and/or pregnancy:
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—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
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