Studies conducted by Planned Parenthood's Guttmacher Institute indicate that two consenting and fertile adults have only a 3 percent chance of pregnancy from an act of intercourse. They also indicate there are factors involved in a rape which further reduce these chances for rape victims. The Guttmacher Institute says 14,000 abortions per year are due to rape or incest, which amounts to just over 1 percent of all abortions. Other studies show that pregnancies due to rape are much rarer than is generally thought, perhaps as few as one in a thousand cases. Furthermore, since conception doesn't occur immediately after intercourse, pregnancy can be prevented in the great majority of rape cases by medical treatment that removes the semen before an ovum can be fertilized.