You are scared about a recent sexual encounter, and wonder if you have a chance of pregnancy. Is it worth getting emergency contraception, or just hope for the best?

Emergency contraception pills (ECP) are an option for many women. Whatever the reason for your "pregnancy scare", you can use ECP within 120 hours (5 days) after unprotected sex to decrease your chances of unintended pregnancy. It is safe, effective, available without prescription for women (and men can purchase it, too) for those 17 and older in the U.S.

ECP is highly effective for a "last chance" pregnancy prevention. Depending on many variables, most reports "estimate effectiveness of ECPs (reduction in a woman's chance of pregnancy) are between 56% to 89%". (Trussel, et al.) Compared this to condoms at (up to) 98 percent effective, and birth control pills at 99 percent effective, ECPs are effective but are not recommended for frequent use because they are not as effective other forms of birth control pills (BCP).

ECPs have been proven safe for women. They also are safe for the fetus, as if you are already pregnant, they do not terminate a pregnancy. "ECPs will not work if a woman is already pregnant, and will not harm the woman or her fetus. There is no time when the emergency contraceptive pills available in the United States would end a pregnancy once it has started. Hormonal emergency contraceptive pills don’t have any effect if you are already pregnant." (Princeton University)

Similarly, ECPs and BCPs also have not shown to have any teratogenic effects (birth defects) if taken by women who are already pregnant.

You may have the following non-harmful side effects after using ECP:

Many women want to know when they can expect their next period after taking ECPs. Some women experience bleeding, and are confused if it is their period (thus they can relax knowing that they are not pregnant), or a side effect. After taking ECP, If you experience: