"7. Can Plan B terminate pregnancy?
Plan B is used to stop the pregnancy before it actually happens. It cannot terminate an already established pregnancy and so don't take this medication if you are pregnant."
This is from the makers website.
Also from makers website: How does Plan B work (mechanism of action)?
Plan B is believed to act as an emergency contraceptive principally by preventing ovulation or fertilization (by altering tubal transport of sperm and/or ova). In addition, it may inhibit implantation by altering the endometrium. Plan B is not effective if a woman is pregnant. Plan B is a contraceptive and cannot terminate an established pregnancy.
Very clever how they say "in addition, it may inhibit implantation..." then go on to say "Plan B cannot terminate a pregnancy."
Life is created at fertilization. Orwell would be proud of Barr.