[hocndoc]

The AMA hasn't redefined the word, the American College of Gynecologists and Obstetricians and many pro-abortion researchers and abortionists have attempted to do so. But, there are obstacles, such as prior literature and common usage.

However, I don't believe that contraceptives were the motive. History will show that the need to justify the ethics of the destruction of embryos resulting from in vitro fertilization and pre-implantation manipulation of the embryo led to an attempt to find new uses for old words.

There's no actual evidence that the embryo within a woman who has has ovulated while on exogenous hormones is treated any differently than the embryo of a woman who has not been on contraceptives, except that passage through the fallopian tubes may be slowed with the use of progesterone-only pills. No one has done the experiments to show that oral combination contraceptives cause abortions or that the effect of OCP hormones can over-ride the hormones from the corpus luteum after ovulation.

[Aquinasfan]

No one has done the experiments to show that oral combination contraceptives cause abortions

It's my understanding that "the pill" thins the uterine lining which in some cases serves to prevent implantation, thus causing an abortion.