Many conservatives and Christian fundamentalists refer to birth control pills as "abortifacients," because of a mistaken belief that if the user happens to already be pregnant, taking the pills will cause an abortion. 1/
This is because b-c pills were long considered to have the effect of preventing fertilized eggs from implanting in the uterus - which, according to some definitions, is after pregnancy has begun, and after according to others. 2/
In reality, many fertilized eggs never implant and are ejected from the body, even without birth control pills. Most women who experience this never even know. And the science is far from settled whether birth control makes this more likely. 3/
So, the pill MAY prevent fertilized eggs from implanting, but we don't know for sure. And a fertilized egg that doesn't implant MAY be considered an aborted pregnancy, or it may not, depending on your definition of the beginning of pregnancy. And finally... 4/
...Even if the pill did cause fertilized eggs not to implant, it would simply somewhat increase the rate of a process that often happens naturally. For whatever reason, many eggs don't implant. Whether this is a miscarriage or simply failing to get pregnant is debatable. 5/
