Sperm can live in a woman’s body for five or even six days, so fertilization and pregnancy may not occur until days after having sex. That’s why EC may still be effective in preventing pregnancy days later. However, “the sooner the better” rule applies to emergency contraception. When taken within 24 hours, EC is 95% effective in preventing pregnancy, but that percentage drops to 75% within 72 hours and just keeps dropping.
Thursday, June 30, 2011