If doubling up on your birth control pills an affective way against pregnancy?

Assuming you are considering the use of double BC after unprotected sex, technically you cannot prevent a pregnancy if conception has already occured. But you can cause a uterus linning to be unfriendly to implantation, and thus cause a very early misscarriage or abortion.

There are some who have redifined conception or pregnancy to be when the fertilized egg or zygote inplants in the uterus lining or endometrium. Thus under this defining pregnancy has not occurred. But a zygote is a zygote and implanted or not genetics separte and unique from the mother and father have been created dispite implantation. You decide if taking extra Birth Control is an abortion or not... yes... it does work.