(Published September 2011)
Emergency Contraception
Description
Emergency contraception can prevent pregnancy after unprotected intercourse. Advance provision of EC is recommended for all women at risk for unintended pregnancy. Two forms of EC are available in the United States: pills or the Copper T IUD.
EC Pills
The EC pills available in the United States are:
- Plan B® One-Step – single 1.5-mg levonorgestrel pill
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Next ChoiceTM – two 0.75-mg levonorgestrel pills
- ella® – single 30-mg ulipristal acetate pill
Use
- The Next Choice product labeling states that the first tablet should be taken orally as soon as possible within 72 hours after unprotected intercourse.102 The second tablet should be taken 12 hours after the first dose.
- Research shows that taking both pills at once increases compliance without increasing side effects or decreasing efficacy.103,104
- The product labeling for Plan B One-Step states that one pill should be taken within 72 hours after unprotected intercourse.105
- Research indicates that both the single dose and the two-dose formulations of levonorgestrel are effective up to 120 hours after unprotected intercourse.104
- Ella is approved for use up to 120 hours after unprotected sex. While the effectiveness of progestin-only pills declines with delay in treatment, the effectiveness of ella does not (up to 120 hours).106
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Dispelling Myths About Emergency Contraception
It's important for women and their providers to have accurate information about EC.
- EC pills do not harm an existing pregnancy.107
- EC pills and the copper IUD for EC do not cause an abortion.107
- Provision of EC in advance is not associated with an increase in unprotected intercourse.108
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Effectiveness*
- The two available levonorgestrel formulations (Plan B One-Step and Next Choice) are equally effective in preventing pregnancy and have similar side effect profiles.104,109,110
- When taken 72 to 120 hours after sex, ulipristal acetate (ella) prevents significantly more pregnancies than Plan B; the odds of getting pregnant after taking Ella 72 to 120 hours after sex is about half the odds of getting pregnant after taking Plan B during a similar time period.111
- The effectiveness of progestin-only pills declines with delay in treatment, whereas the effectiveness of ella does not (for up to 120 hours).107
*The exact effectiveness of emergency contraceptive pills is difficult to measure, and some researchers believe the effectiveness may be lower than that reported on package labels. To find out more about studies evaluating the effectiveness of emergency contraception, read our thorough and up-to-date academic review of the medical and social science literature here)
Risks, Contraindications, and Precautions
Given the single-dose nature of EC pills, most experts feel there are no risks considered to be contraindications.
Side Effects
Some women experience nausea, fatigue, and headache.
Advantages
- Highly effective
- Discreet
- Reversible
Disadvantages
- Requires prescription if younger than age 17 (for all ages if ella is used)
- No protection against STIs
Counseling Messages
- Patients should obtain emergency contraception in advance and keep it available for use if needed.
- Highly effective reversible ongoing contraceptive options are available.
- With valid identification showing an age of 17 or older, EC can be purchased at a pharmacy.
- Females who are younger than age 17 require a prescription. Ella requires a prescription regardless of age.
- This method does not protect against STIs.
Copper IUD for EC
Use
If the time of ovulation cannot be estimated, the copper IUD can be used as EC up to 5 days after unprotected intercourse. If the time of ovulation can be estimated, the copper IUD can be placed more than 5 days after intercourse but not more than 5 days after ovulation.5 The LNG IUS cannot be used for EC.
Effectiveness
Copper IUD EC is more than 99 percent effective in reducing pregnancy risk.110,112
Risks, Side Effects, Contraindications, and Precautions
Given the ongoing use of the copper IUD for contraception after EC use, the risks, side effects, contraindications, and precautions are similar to those described for contraceptive use of the copper IUD (see section on copper IUD). In addition, see the table below.
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Category 4
(unacceptable health risk if the contraceptive method is used) |
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Category 3
(theoretical or proven risks usually outweigh the advantages of using the method) |
- Rape with high risk for STIs
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Source: Reference 5 |
*Refer to the copper T IUC section for a list of contraindications and precautions for ongoing use.
Advantages
- Highly effective
- Reversible
Disadvantages
- Requires placement by trained health care provider
- No protection against STIs
Counseling Messages
- Patients should obtain emergency contraception pills in advance and keep them available for use if needed.
- Highly effective reversible ongoing contraceptive options are available.
- With valid identification showing an age of 17 or older, EC can be purchased at a pharmacy.
- Females who are younger than age 17 require a prescription. Ella requires a prescription regardless of age.
- This method does not protect against STIs.