Whose Time Has Come Allan Rosenfield, MD Unplanned pregnancy is a reproductive health problem of tremendous significance worldwide. Similarly, there are large percentages of unplanned pregnancies throughout the developing world. Where it is illegal, abortion is most commonly carried out clandestinely, often at very high risk to the health of the women. Unplanned pregnancies result from unexpected midcycle intercourse, from failure to use a regular method of contraception, or from method failure, such as condom breakage.
Emergency contraception is used to prevent pregnancy after unprotected midcycle sexual intercourse.
It was first used for women who had been raped, but later became available for unprotected intercourse, no matter the reason. Various methods are available, the most common being the original Yuzpe method in which oral contraceptives are used, in a higher dose than usual, within 72 hours of intercourse and then again 12 hours later. The mechanism of action of EC has been debated, and those opposed to abortion maintain that it is simply another abortifacient. But taken within 72 hours of midcycle unprotected intercourse, the major action of the Yuzpe method is interference with ovulation, with fertilization or, in some cases with implantation. There are no data to suggest that oral contraceptives have any effect on an already implanted ovum.