ECPs may also help sexually active young people realize that they need to begin using regular contraception. It is important that young men and women know about ECPs, so that if they have unprotected sex and find themselves facing the possibility of an unplanned pregnancy and its health and social consequences, they know that they can still act to prevent this occurrence. A woman using ECPs takes two doses, twelve hours apart, of particular formulations of regular OCs, normally containing estrogen and a progestin. With either regimen, the first dose is taken as soon after unprotected sex as possible, but no later than 72 hours afterwards. 5 Informational materials, such as Pathfinder International's training curriculum, provide detailed information on the formulation, dosages, and clinical management of emergency contraceptive pills.
Some women experience nausea and vomiting for a day or so when using ECPs.
Other possible side effects include spotting, temporary breast tenderness, headaches, dizziness and fatigue. Depending on when in her cycle a woman uses them, ECPs may work in several ways. Studies show that if a woman has not ovulated, ECPs can stop or delay ovulation. Delaying ovulation may be the main or only mechanism of action. Although there is little evidence, researchers hypothesize that ECPs may also work in other ways.