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Emergency Contraception


How Effective Is Emergency Contraception?

If Plan B One-Step is taken as directed after unprotected sex, it will decrease the chances of a pregnancy occurring. About 7 out of every 8 women who would have gotten pregnant do not become pregnant. However, research shows that Plan B One-Step starts to lose its effectiveness in women heavier than 165 pounds and is not recommend for anyone over this weight. Instead, an IUD is the suggested option in this group.

In two reported studies, Ella significantly reduced the pregnancy rate from an expected rate of 5.5% and 5.6% to 2.2% and 1.9%, respectively. In a pooled analysis of the data, the effectiveness did not fade for 120 hours after unprotected sex.

An IUD can be up to 99% effective when inserted within 5 to 7 days after unprotected intercourse.

Where Can I Get Emergency Contraception?

Emergency contraceptive pills (ECPs) are available at Planned Parenthood; college, public, and women's health centers; private doctors; and some hospital emergency rooms.

Some doctors will prescribe ECPs over the phone and call the prescription in to a pharmacy. As mentioned above, Plan B One-Step is available at pharmacies without a prescription.

Who Should Not Use ECPs?

Plan B One-Step will not affect an existing pregnancy or cause harm to a fetus. Ella should not be used by women who are already pregnant or may be pregnant. The risk to a human fetus is unknown. Animal studies have demonstrated risk of fetal loss. Also, women who have had clotting disorders or deep venous thrombosis (DVT) should not use Plan B One-Step.

Are There Any Side Effects Associated With Emergency Contraception Pills?

The most common side effects associated with emergency contraception pills include:

Ask your doctor or pharmacist about ways to reduce nausea. They may prescribe some anti-nausea medicine for you to take before you take an ECP.

Does It Protect Against Sexually Transmitted Diseases (STDs)?

No. Emergency contraception will not protect you from contracting an STD, such as HIV, the virus that causes AIDS. The best way to avoid getting STDs is to limit sexual contact to one uninfected partner. If that is not an option, use a latex condom correctly every time you have sex.

WebMD Medical Reference

Reviewed by Nivin Todd, MD on August 12, 2014
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