Unwanted-72 is an emergency morning after contraceptive designed to prevent conception when unplanned sexual intercourse has occurred. It is a mega-dose female hormones that work in one of several way to prevent unwanted pregnancy. The three ways it works are as follows: Prevents/delays release of the ovum (female egg) from the female s ovaries Thickens the mucus lining of the cervix, which prevents/blocks male sperm from entering the uterus Prevents a fertilized egg from traveling down the Fallopian tubes and implanting itself onto the uterus wall, which begins pregnancy. Unwanted 72 is a contraceptive and it can make you pregnant.